Recently, crime prevention is away of important criminal justice policy and police activity also pursuit different change compare to the present times. After modern times, as get to know crime control change, eventually on the basis of experience that crime prevention is best way of crime control, what come out with new sight angle for the role of police is community policing. And emphasis points in police activity are variety of police activity, positive entry of community. In relation to this, we are learning crime prevention of the U.S.A and the program of community policing through crime prevention theory books that published in domestic. Then, there are misunderstanding possibilities that the programs which introduced relation books are doing someways all around the U.S.A In this research two cities san mateo county. california, of the U.S.A made a choice, and is going to search main crime present condition of these cities and really done community policing program or crime prevention program operation case.