Mobile application single sign-on method and device

Disclosed are a mobile application single sign-on method and device. The method comprises: when performing a mobile application single sign-on for the first time, transmitting, by a terminal to an application server and via a pseudo single sign-on server, a first sign-on authentication request including user sign-on information, a package name of a first application and a user identifier, such that the pseudo single sign-on server acquires a pseudo password after the application server authenticates the first sign-on authentication request; when performing the mobile application single sign-on for a second time, acquiring, by the terminal by utilizing the user identifier, the pseudo password from the pseudo single sign-on server for signing on to a second application; and performing, by the terminal and by utilizing the user sign-on information and the pseudo password, the single sign-on to the second application, wherein the user sign-on information of the first application and the second application are the same and are mutually associated via the user identifier. The present invention realizes a single sign-on and a cross-terminal application single sign-on for a plurality of mobile applications.