Disclosed are a method and system for promoting a player character in a sports game using a dualized space. A player character promotion method may include processing a progress of a sports game instance in which at least one player character controlled in response to a user's input participates through a first virtual space configured for the progress of a sports game, providing a user interface for promoting a promotion mode for a given player character between sports game instances, and performing a promotion scenario for a selected player character through a second virtual space different from the first virtual space for the progress of the sports game instance when the promotion mode for the selected player character is activated through the user interface.