This application is directed to a method and an apparatus for associating an application with a network slice, and a communications system. The method includes: obtaining, by a terminal, display instruction information, an identifier of a first network slice that the terminal is allowed to access, and service feature information corresponding to the first network slice. The method further includes: displaying the service feature information corresponding to the first network slice on a first display interface of the terminal based on the display instruction information, and generating a first network slice selection policy when detecting an operation of associating a first application with the first display interface. The first network slice selection policy can include a mapping relationship between the first application and the identifier of the first network slice corresponding to the first display interface.