diff --git a/index.d.ts b/index.d.ts
index 70a48e91..821c3935 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -4,10 +4,10 @@ import { DatePickerIOSProps, StyleProp, ViewStyle } from 'react-native';
 interface IStyle {
 	selectedItemTextColor?: string;
 	selectedItemTextSize?: number;
-	selectedItemTextFontFamily: string;
+	selectedItemTextFontFamily?: string;
 	itemTextColor?: string;
 	itemTextSize?: number;
-	itemTextFontFamily: string;
+	itemTextFontFamily?: string;
 	indicatorColor?: string;
 	hideIndicator?: boolean;
 	indicatorWidth?: number;
@@ -55,4 +55,4 @@ export interface IPropsDatePicker extends DatePickerIOSProps {
 
 export class DatePicker extends React.Component<IPropsDatePicker> {
 	constructor(props: IPropsDatePicker);
-}
\ No newline at end of file
+}