Disclosed is a method of displaying a notification on a device with a plurality of operating systems (OSes) installed therein. The method includes identifying a first OS displayed on a first display of the device among the plurality of OSes, detecting a notification generated in a second OS running in a background of the device among the plurality of OSes, converting the generated notification based on a preset format of the first OS when the notification is generated, and displaying the converted notification on the first display on which the first OS is displayed.