diff --git a/src/calendar/README.zh-CN.md b/src/calendar/README.zh-CN.md
index d4710d487..a74c02f01 100644
--- a/src/calendar/README.zh-CN.md
+++ b/src/calendar/README.zh-CN.md
@@ -251,7 +251,7 @@ export default {
 
 | 参数 | 说明 | 类型 | 默认值 |
 | --- | --- | --- | --- |
-| type | 选择类型:<br>`single`表示选择单个日期，<br>`multiple`表示选择多个日期，<br>`range`表示选择日期区间 | _string_ | `single` |
+| type | 选择类型:<br>`single` 表示选择单个日期，<br>`multiple` 表示选择多个日期，<br>`range` 表示选择日期区间 | _string_ | `single` |
 | title | 日历标题 | _string_ | `日期选择` |
 | color | 主题色，对底部按钮和选中日期生效 | _string_ | `#ee0a24` |
 | min-date | 可选择的最小日期 | _Date_ | 当前日期 |
diff --git a/src/calendar/components/Day.js b/src/calendar/components/Day.tsx
similarity index 77%
rename from src/calendar/components/Day.js
rename to src/calendar/components/Day.tsx
index f27091037..f59fd9b79 100644
--- a/src/calendar/components/Day.js
+++ b/src/calendar/components/Day.tsx
@@ -1,16 +1,43 @@
+import { computed, CSSProperties, PropType } from 'vue';
 import { createNamespace } from '../../utils';
 import { bem } from '../utils';
-import { computed } from 'vue';
 
 const [createComponent] = createNamespace('calendar-day');
 
+export type DayType =
+  | ''
+  | 'start'
+  | 'start-end'
+  | 'middle'
+  | 'end'
+  | 'selected'
+  | 'multiple-middle'
+  | 'multiple-selected'
+  | 'disabled'
+  | 'placeholder';
+
+export type DayItem = {
+  date?: Date;
+  text?: string | number;
+  type?: DayType;
+  topInfo?: string;
+  className?: unknown;
+  bottomInfo?: string;
+};
+
 export default createComponent({
   props: {
-    item: Object,
     color: String,
     index: Number,
-    offset: Number,
     rowHeight: String,
+    offset: {
+      type: Number,
+      default: 0,
+    },
+    item: {
+      type: Object as PropType<DayItem>,
+      required: true,
+    },
   },
 
   emits: ['click'],
@@ -18,7 +45,7 @@ export default createComponent({
   setup(props, { emit }) {
     const style = computed(() => {
       const { item, index, color, offset, rowHeight } = props;
-      const style = {
+      const style: CSSProperties = {
         height: rowHeight,
       };
 
@@ -92,7 +119,7 @@ export default createComponent({
           role="gridcell"
           style={style.value}
           class={[bem('day', type), className]}
-          tabindex={type === 'disabled' ? null : -1}
+          tabindex={type === 'disabled' ? undefined : -1}
           onClick={onClick}
         >
           {renderContent()}
diff --git a/src/calendar/components/Header.js b/src/calendar/components/Header.tsx
similarity index 100%
rename from src/calendar/components/Header.js
rename to src/calendar/components/Header.tsx
diff --git a/src/calendar/components/Month.js b/src/calendar/components/Month.tsx
similarity index 80%
rename from src/calendar/components/Month.js
rename to src/calendar/components/Month.tsx
index 9af7decce..b2bb67e82 100644
--- a/src/calendar/components/Month.js
+++ b/src/calendar/components/Month.tsx
@@ -1,4 +1,4 @@
-import { ref, computed } from 'vue';
+import { ref, computed, PropType } from 'vue';
 
 // Utils
 import { addUnit, setScrollTop, createNamespace } from '../../utils';
@@ -18,26 +18,37 @@ import { useExpose } from '../../composables/use-expose';
 import { useHeight } from '../../composables/use-height';
 
 // Components
-import Day from './Day';
+import Day, { DayItem, DayType } from './Day';
 
 const [createComponent] = createNamespace('calendar-month');
 
+export type CalendarType = 'single' | 'range' | 'multiple';
+
 export default createComponent({
   props: {
-    date: Date,
-    type: String,
+    type: String as PropType<CalendarType>,
     color: String,
-    minDate: Date,
-    maxDate: Date,
     showMark: Boolean,
     rowHeight: [Number, String],
-    formatter: Function,
+    formatter: Function as PropType<(item: DayItem) => DayItem>,
     lazyRender: Boolean,
-    currentDate: [Date, Array],
+    currentDate: [Date, Array] as PropType<Date | Date[]>,
     allowSameDay: Boolean,
     showSubtitle: Boolean,
     showMonthTitle: Boolean,
     firstDayOfWeek: Number,
+    date: {
+      type: Date as PropType<Date>,
+      required: true,
+    },
+    minDate: {
+      type: Date as PropType<Date>,
+      required: true,
+    },
+    maxDate: {
+      type: Date as PropType<Date>,
+      required: true,
+    },
   },
 
   emits: ['click', 'update-height'],
@@ -67,7 +78,7 @@ export default createComponent({
 
     const getTitle = () => title.value;
 
-    const scrollIntoView = (body) => {
+    const scrollIntoView = (body: Element) => {
       const el = props.showSubtitle ? daysRef.value : monthRef.value;
 
       const scrollTop =
@@ -78,9 +89,11 @@ export default createComponent({
       setScrollTop(body, scrollTop);
     };
 
-    const getMultipleDayType = (day) => {
-      const isSelected = (date) =>
-        props.currentDate.some((item) => compareDay(item, date) === 0);
+    const getMultipleDayType = (day: Date) => {
+      const isSelected = (date: Date) =>
+        (props.currentDate as Date[]).some(
+          (item) => compareDay(item, date) === 0
+        );
 
       if (isSelected(day)) {
         const prevDay = getPrevDay(day);
@@ -103,8 +116,8 @@ export default createComponent({
       return '';
     };
 
-    const getRangeDayType = (day) => {
-      const [startDay, endDay] = props.currentDate;
+    const getRangeDayType = (day: Date) => {
+      const [startDay, endDay] = props.currentDate as Date[];
 
       if (!startDay) {
         return '';
@@ -130,9 +143,11 @@ export default createComponent({
       if (compareToStart > 0 && compareToEnd < 0) {
         return 'middle';
       }
+
+      return '';
     };
 
-    const getDayType = (day) => {
+    const getDayType = (day: Date): DayType => {
       const { type, minDate, maxDate, currentDate } = props;
 
       if (compareDay(day, minDate) < 0 || compareDay(day, maxDate) > 0) {
@@ -140,7 +155,7 @@ export default createComponent({
       }
 
       if (currentDate === null) {
-        return;
+        return '';
       }
 
       if (Array.isArray(currentDate)) {
@@ -151,11 +166,13 @@ export default createComponent({
           return getRangeDayType(day);
         }
       } else if (type === 'single') {
-        return compareDay(day, currentDate) === 0 ? 'selected' : '';
+        return compareDay(day, currentDate as Date) === 0 ? 'selected' : '';
       }
+
+      return '';
     };
 
-    const getBottomInfo = (dayType) => {
+    const getBottomInfo = (dayType: DayType) => {
       if (props.type === 'range') {
         if (dayType === 'start' || dayType === 'end') {
           return t(dayType);
@@ -179,7 +196,7 @@ export default createComponent({
     };
 
     const placeholders = computed(() => {
-      const rows = [];
+      const rows: DayItem[] = [];
       const count = Math.ceil((totalDay.value + offset.value) / 7);
       for (let day = 1; day <= count; day++) {
         rows.push({ type: 'placeholder' });
@@ -188,7 +205,7 @@ export default createComponent({
     });
 
     const days = computed(() => {
-      const days = [];
+      const days: DayItem[] = [];
       const year = props.date.getFullYear();
       const month = props.date.getMonth();
 
@@ -196,7 +213,7 @@ export default createComponent({
         const date = new Date(year, month, day);
         const type = getDayType(date);
 
-        let config = {
+        let config: DayItem = {
           date,
           type,
           text: day,
@@ -213,7 +230,7 @@ export default createComponent({
       return days;
     });
 
-    const renderDay = (item, index) => (
+    const renderDay = (item: DayItem, index: number) => (
       <Day
         item={item}
         index={index}
diff --git a/src/calendar/index.js b/src/calendar/index.tsx
similarity index 84%
rename from src/calendar/index.js
rename to src/calendar/index.tsx
index 947b4c048..591b419e4 100644
--- a/src/calendar/index.js
+++ b/src/calendar/index.tsx
@@ -1,7 +1,7 @@
-import { ref, watch, reactive, computed } from 'vue';
+import { ref, watch, reactive, computed, PropType, TeleportProps } from 'vue';
 
 // Utils
-import { pick, getScrollTop } from '../utils';
+import { pick, getScrollTop, ComponentInstance } from '../utils';
 import { isDate } from '../utils/validate/date';
 import {
   t,
@@ -23,28 +23,33 @@ import { useRefs } from '../composables/use-refs';
 import { useExpose } from '../composables/use-expose';
 
 // Components
-import Popup from '../popup';
+import Popup, { PopupPosition } from '../popup';
 import Button from '../button';
 import Toast from '../toast';
-import Month from './components/Month';
+import Month, { CalendarType } from './components/Month';
 import Header from './components/Header';
 
+// Types
+import type { DayItem } from './components/Day';
+
 export default createComponent({
   props: {
     show: Boolean,
     title: String,
     color: String,
     readonly: Boolean,
-    teleport: [String, Object],
-    formatter: Function,
+    teleport: [String, Object] as PropType<TeleportProps['to']>,
+    formatter: Function as PropType<(item: DayItem) => DayItem>,
     rowHeight: [Number, String],
     confirmText: String,
     rangePrompt: String,
-    defaultDate: [Date, Array],
+    // TODO: remove any
+    // see: https://github.com/vuejs/vue-next/issues/2668
+    defaultDate: [Date, Array] as any,
     allowSameDay: Boolean,
     confirmDisabledText: String,
     type: {
-      type: String,
+      type: String as PropType<CalendarType>,
       default: 'single',
     },
     round: {
@@ -52,7 +57,7 @@ export default createComponent({
       default: true,
     },
     position: {
-      type: String,
+      type: String as PropType<PopupPosition>,
       default: 'bottom',
     },
     poppable: {
@@ -96,14 +101,14 @@ export default createComponent({
       default: true,
     },
     minDate: {
-      type: Date,
+      type: Date as PropType<Date>,
       validator: isDate,
       default: () => new Date(),
     },
     maxDate: {
-      type: Date,
+      type: Date as PropType<Date>,
       validator: isDate,
-      default() {
+      default: () => {
         const now = new Date();
         return new Date(now.getFullYear(), now.getMonth() + 6, now.getDate());
       },
@@ -111,7 +116,7 @@ export default createComponent({
     firstDayOfWeek: {
       type: [Number, String],
       default: 0,
-      validator: (val) => val >= 0 && val <= 6,
+      validator: (val: number) => val >= 0 && val <= 6,
     },
   },
 
@@ -119,7 +124,7 @@ export default createComponent({
 
   setup(props, { emit, slots }) {
     const limitDateRange = (
-      date,
+      date: Date,
       minDate = props.minDate,
       maxDate = props.maxDate
     ) => {
@@ -167,7 +172,7 @@ export default createComponent({
       return limitDateRange(defaultDate);
     };
 
-    let bodyHeight;
+    let bodyHeight: number;
 
     const bodyRef = ref();
 
@@ -176,10 +181,10 @@ export default createComponent({
       currentDate: getInitialDate(),
     });
 
-    const [monthRefs, setMonthRefs] = useRefs();
+    const [monthRefs, setMonthRefs] = useRefs<ComponentInstance>();
 
     const dayOffset = computed(() =>
-      props.firstDayOfWeek ? props.firstDayOfWeek % 7 : 0
+      props.firstDayOfWeek ? +props.firstDayOfWeek % 7 : 0
     );
 
     const months = computed(() => {
@@ -201,10 +206,10 @@ export default createComponent({
 
       if (currentDate) {
         if (props.type === 'range') {
-          return !currentDate[0] || !currentDate[1];
+          return !(currentDate as Date[])[0] || !(currentDate as Date[])[1];
         }
         if (props.type === 'multiple') {
-          return !currentDate.length;
+          return !(currentDate as Date[]).length;
         }
       }
 
@@ -267,7 +272,7 @@ export default createComponent({
       }
     };
 
-    const scrollToDate = (targetDate) => {
+    const scrollToDate = (targetDate: Date) => {
       raf(() => {
         months.value.some((month, index) => {
           if (compareMonth(month, targetDate) === 0) {
@@ -291,7 +296,7 @@ export default createComponent({
       const { currentDate } = state;
       if (currentDate) {
         const targetDate =
-          props.type === 'single' ? currentDate : currentDate[0];
+          props.type === 'single' ? currentDate : (currentDate as Date[])[0];
         scrollToDate(targetDate);
       } else {
         raf(onScroll);
@@ -316,7 +321,7 @@ export default createComponent({
       scrollIntoView();
     };
 
-    const checkRange = (date) => {
+    const checkRange = (date: [Date, Date]) => {
       const { maxRange, rangePrompt } = props;
 
       if (maxRange && calcDateNum(date) > maxRange) {
@@ -331,21 +336,21 @@ export default createComponent({
       emit('confirm', copyDates(state.currentDate));
     };
 
-    const select = (date, complete) => {
-      const setCurrentDate = (date) => {
+    const select = (date: Date | Date[], complete?: boolean) => {
+      const setCurrentDate = (date: Date | Date[]) => {
         state.currentDate = date;
         emit('select', copyDates(state.currentDate));
       };
 
       if (complete && props.type === 'range') {
-        const valid = checkRange(date);
+        const valid = checkRange(date as [Date, Date]);
 
         if (!valid) {
           // auto selected to max range if showConfirm
           if (props.showConfirm) {
             setCurrentDate([
-              date[0],
-              getDayByOffset(date[0], props.maxRange - 1),
+              (date as Date[])[0],
+              getDayByOffset((date as Date[])[0], +props.maxRange - 1),
             ]);
           } else {
             setCurrentDate(date);
@@ -361,8 +366,8 @@ export default createComponent({
       }
     };
 
-    const onClickDay = (item) => {
-      if (props.readonly) {
+    const onClickDay = (item: DayItem) => {
+      if (props.readonly || !item.date) {
         return;
       }
 
@@ -372,7 +377,7 @@ export default createComponent({
 
       if (type === 'range') {
         if (!currentDate) {
-          select([date, null]);
+          select([date]);
           return;
         }
 
@@ -384,12 +389,12 @@ export default createComponent({
           if (compareToStart === 1) {
             select([startDay, date], true);
           } else if (compareToStart === -1) {
-            select([date, null]);
+            select([date]);
           } else if (props.allowSameDay) {
             select([date, date], true);
           }
         } else {
-          select([date, null]);
+          select([date]);
         }
       } else if (type === 'multiple') {
         if (!currentDate) {
@@ -398,13 +403,15 @@ export default createComponent({
         }
 
         let selectedIndex;
-        const selected = state.currentDate.some((dateItem, index) => {
-          const equal = compareDay(dateItem, date) === 0;
-          if (equal) {
-            selectedIndex = index;
+        const selected = state.currentDate.some(
+          (dateItem: Date, index: number) => {
+            const equal = compareDay(dateItem, date) === 0;
+            if (equal) {
+              selectedIndex = index;
+            }
+            return equal;
           }
-          return equal;
-        });
+        );
 
         if (selected) {
           const [unselectedDate] = currentDate.splice(selectedIndex, 1);
@@ -419,11 +426,11 @@ export default createComponent({
       }
     };
 
-    const togglePopup = (val) => {
-      emit('update:show', val);
+    const togglePopup = (value: boolean) => {
+      emit('update:show', value);
     };
 
-    const renderMonth = (date, index) => {
+    const renderMonth = (date: Date, index: number) => {
       const showMonthTitle = index !== 0 || !props.showSubtitle;
       return (
         <Month