A method for applying for media transmission permission, and a method and an apparatus for canceling media transmission permission are provided. The method for applying for media transmission permission includes: determining, by a first terminal, that a second terminal needs to transmit media data; and sending, by the first terminal, media transmission permission request indication information to a mission critical service (MCS) server, where the media transmission permission request indication information is used to instruct the MCS server to grant media transmission permission to the second terminal.