This application provides a media file encapsulating method, a media file decapsulating method, and related devices. The media file encapsulating method includes: acquiring a media stream of a target media content in a corresponding application scenario; encapsulating the media stream to generate an encapsulation file of the media stream, the encapsulation file including a first application scenario type field, the first application scenario type field being used for indicating the application scenario corresponding to the media stream; and transmitting the encapsulation file to a first device for the first device to determine the application scenario corresponding to the media stream according to the first application scenario type field and determine at least one of a decoding method and a rendering method of the media stream according to the application scenario corresponding to the media stream. This method can distinguish different application scenarios in the encapsulation of media files.