In the era of big data，citizens’ personal information security is facing unprecedented challenges. The collection，analysis，and use of personal information of citizens has become simpler as technology has matured. Driven by various interests，the unauthorized collection and malicious use of personal information of citizens have become a problem despite repeated prohibitions. Even some public departments have leaked a large amount of personal information in the process of providing services，causing violations of citizens’ rights. China has continuously strengthened the protection of citizens’ personal information in terms of legislation，law enforcement and justice，and has achieved remarkable results. In the future，it is necessary to further strengthen the protection of personal information of citizens from the aspects of legislation，justice，supervision and the cultivation of cybersecurity personnel.