A method and a system for remotely controlling a smart television based on a mobile terminal and the mobile terminal are disclosed. The method includes: detecting a state of the smart television every predetermined time interval by the mobile terminal, and receiving a command input from a user to acquire a type of an audience watching the smart television; determining whether a current playing time, a playing content and a playing duration conform to conditions preset by a user, when the audience watching the smart television is a minor; and detecting whether the smart television is in a turned-on state when the audience watching the smart television is an older person.