In the age of big data, while the rapid development of information technology has brought convenience to people's lives, there have also been problems such as illegal collection, abuse, trading, and disclosure of personal information, especially the increasing incidence of crimes against citizens' personal information, which has brought great challenges to the protection of citizens' personal information. Recently, the Supreme People's Court released the 35th batch of four guiding cases, all of which are criminal cases of citizens' personal information protection, involving the scope and nature of citizens' personal information protected by criminal law, such as face recognition information, resident ID card information, WeChat and other social media accounts, mobile phone verification codes, etc. Personal information protection concerns people's sense of security. In recent years, our country has been making efforts from legislation, law enforcement, justice and other aspects to weave a dense protective network for personal information security. The criminal law specially stipulates the crime of infringing on citizens' personal information, which provides a powerful weapon for severely punishing the black hands that extend to citizens' personal information. The Supreme People's Court and the Supreme People's Procuratorate have specially issued relevant judicial interpretations, which have made more comprehensive and systematic provisions on the criteria for conviction and sentencing of crimes against citizens' personal information and the application of relevant laws. At present, the illegally obtained personal information of citizens has not only included identity information, telephone number, home address, etc., but also extended to mobile phone address book, SMS, network account and password, shopping records, travel records, etc. The law itself has the characteristics of principle, generality and lag. In the face of the variety of infringements on citizens' personal information, how to identify the nature of relevant acts and how to accurately convict and sentence, is not only related to the correct application of the law, but also related to the realization of fairness and justice, and also tests the wisdom of the judiciary. This time, the Supreme People's Court issued a guiding case to clarify the rules for judging similar cases, which is of great practical and guiding significance. For example, it recognized that the face information belongs to the personal information of citizens specified in the criminal law, and the information of resident identity cards are sensitive information as a whole; Sell the verification code and corresponding mobile phone number obtained in the process of providing services to others. If the circumstances are serious, they will be convicted and punished according to the crime of infringing on citizens' personal information. These guidance cases are not only a true portrayal of the judiciary's protection of citizens' personal information, but also a vivid teaching material for law popularization. The protection of personal information is the most direct and realistic interest issue that the masses of the people are most concerned about. It is expected that the judicial authorities will further play their functions, continue to intensify the fight against relevant crimes, strengthen judicial cooperation in law enforcement, better adapt to the situation, use the law, effectively safeguard the personal information security, property and personal rights of the people, and fully respect, realize and protect the rights of the people in the digital society. (Liu Xinshe)