This research was to find the impact of the Implementation of Societal Security Promotion Plan carried out by Tehran Province Police Command on People’s trust in Police in the Karaj Downtown in 2008. The goal of the research was to give out information about the scope of effectiveness of Societal Security Promotion Plan (SSPP) especially on the people’s confidence to police and its reaction on the Karaj city community, crime reduction, increase of clients satisfaction of police, increase in people’s cooperation, increase of police authority, increase in feeling of security, people’s law-abiding, …. In order to implement the survey, the dimensions and different aspects of the issue was scrutinized by theoretical bases. Then, a self-made scale, with sufficient reliability and validity was used to measure the feeling of security, people’s cooperation, people law-abiding, and police authority. Data was analyzed through t andc2 tests by using SPSS. The results showed that there were significant relationship between SSPP and feeling of security, people's cooperation, people law-abiding, and police authority.