The present invention discloses an account number upgrading method and apparatus for a specified platform. The method comprises: when a user uses a first-type account number to log in a specified platform on a terminal device, determining whether a second-type account number exists on the terminal device; if the second-type account number exists, displaying the existing second-type account number for the user to select; if the second-type account number does not exist, displaying a second-type account number login page for the user to input the existing second-type account number or register a new second-type account number; and mapping the second-type account number that is selected by the user, input by the user or registered by the user with user data under the first-type account number of the user, to enable the user to use the second-type account number to log in the specified platform subsequently. Therefore, when the account number used for logging in the specified platform needs to be upgraded, on the basis of reducing the manual operation process of the user as much as possible, the account number upgrading method and apparatus for the specified platform provided by the present invention provide more efficient, convenient and visual account upgrading experience for the user.