In the era of big data，crimes committed against or using citizens’ personal information have piled up. Once personal information is collected or used maliciously，it will not only damage the personal dignity of the information subject，but may also cause property loss. In this context，the criminal law and judicial interpretation have been constantly regulating and improving the crime of infringement on citizens’ personal information. However，in practice，there are still differences in the understanding and application of legal norms，resulting in difficulties in the trial of cases. This paper clarifies the criminal concept of citizens’ personal information，analyzes the problems existing in the trial of infringement of citizens’ personal information from the two dimensions of legal norms and judicial practice and puts forward targeted opinions and suggestions from the perspective of the identification standard of “serious circumstances”.