The invention discloses an implicit identity authentication method for a mobile intelligent terminal, which comprises the following steps that: a mobile intelligent terminal authentication service system sets a password with a certain length and legal WiFi, and collects touch behavior data when the password is set, and the touch behavior data is stored in a database after being processed by a weight-based dynamic regularization algorithm; the legality of the WiFi environment is monitored in real time; a legal WiFi environment user can automatically enter the mobile intelligent terminal to check information without inputting a password; an illegal WiFi environment user needs to input a password, touch behavior data generated when the password is input are compared with touch behavior data stored in a database according to a weight-based dynamic regularization algorithm, the legality of the identity of the user is determined, and the user enters a mobile intelligent terminal legally to check information; according to the invention, the existing authentication mechanism is enhanced in convenience and security, and the user can be prevented from frequently inputting a password.