English translation (not machine translation, the adoption of an additional 100 points) Reward points: 100 - still 14 days away from the issue of the end of 2 hours Abstract Privacy is an important civil right, since 1890, official U.S. scholar has proposed the concept of privacy, right to privacy has aroused extensive attention. Technology development, production and changed the human way of life. The information age, in people's lives convenient, but also all the time not a threat to people's privacy. At the same time, gradually increase the privacy of citizens awareness of the world's countries are increasingly concerned about privacy issues. Criminal investigation is an important aspect of investigating authorities in collecting evidence against the suspects seized in the process of inevitable conflict with the privacy of citizens. Especially with the development of society, the growing number of crimes, criminal means more intelligent, subtle, organized and complex, relying on traditional means of investigation have not effectively deter crime. Faced with this situation, more and more serious investigation of violations of civil right to privacy means to be widely used, the privacy of citizens facing serious threats. For the realization of the fight against crime and the protection of human rights "win-win" must be right to some extent detection limit, and to strengthen the protection of citizen privacy in the criminal investigation. In this paper, the concept of privacy, analyzes the relationship between the criminal investigation of citizen privacy, in the national criminal investigation of citizen privacy protection system based on the study, analysis of the criminal investigation of citizen privacy, the paper proposes reforms , seek to establish an effective way to protect citizens privacy