Explored the issues of personal information leakage and privacy infringement through two cases. In the first case, a woman reported to the police for receiving harassing phone calls that leaked personal information, and the police imposed a fine on the car sales company involved. The second case involves a little boy who randomly filmed videos on a bus, which a woman believed violated her privacy. The police educated the little boy and explained the legal boundaries of privacy rights. The chapter emphasizes the importance of personal information security in the era of big data and reminds the public to raise awareness of privacy protection. At the same time, Article 42 of the Law of the People's Republic of China on Public Security Administration Punishments was cited to clarify the legal consequences of infringing on the privacy of others.