The invention discloses a method for protecting privacy of identity information based on sensitive information measurement. The method comprises the comprises the following steps of S1, determining input and output; S2, defining and calculating identity importance degree; S3, optimizing the identity importance; S4, calculating a sensitive information disclosing matrix, a minimum 
attack set and an information disclosing probability; S5, determining a generalizing function, and generalizing a dataset; S6, establishing a background knowledge 
attack-avoidance 
privacy protection model; S7, describing a (gamma, eta)-Risk 
anonymity algorithm, inputting an original dataset D, and outputting an 
anonymity dataset D'; S8, introducing a 
confidence interval, controlling the high-probability 
inference attack of an attacking party within the specified 
confidence interval, so as to avoid a user using an attribute 
distribution function to calculate the identity information of the user, calculate features, and perform high-probability 
inference attack. The method has the advantages that the problem of difficulty in effectively treating the privacy information attack based on background knowledge attack in the existing 
privacy protection method is solved, and the key identity and identity sensitive information are more comprehensively and effectively protected.