The application provides an example user interface switching method and an example terminal. The method includes, after the terminal triggers a trusted user interface (TUI) display request of a client application (CA) according to a first operation on a CA interface by a user, the terminal switches a display environment of the CA from a rich execution environment (REE) to a trusted execution environment (TEE) according to the TUI display request, and then displays a trusted application (TA) interface that is of the CA and that is in the TEE. The method also includes performing, by the user, an operation of inputting sensitive information on the TA interface.