A user mode control method and system based on iris recognition for mobile terminal are provided. When the mobile terminal receives an operation instruction of a user to start a display screen, iris feature data of the current user are scanned. The iris feature data of the current user are matched with iris feature data of users collected in advance, and the corresponding user mode is started when the match succeeds. The user mode control method and system prevents a stranger from accessing private data, and greatly improves security of the user data.