Major criminological theories explaining neighborhood-level crime differences consistently point out that residents’ activities are a key factor in crime prevention. In addition, prior research suggests two conditions that can lead to successful residents’ participation in crime prevention activities. First, residents’ active participation should be guaranteed. Second, crime prevention should be an incidental purpose of the residents’ community. Meanwhile, the current neighborhood watch programs have the following limitations. First, the activities have focused disproportionately on the patrol to cope with the street crime. This type of activities have limitations to properly cope with new types of crime. Second, there has been a lack of effective activities by staying in the position of an assistant to the police. Third, the participation of residents are decreasing. To solve these problems, social media-based resident-participating crime prevention activities need to be considered. The social media-based activities have the following characteristics. First, local problems are solved with collective intelligence. Second, they promotes surveillance through real-time communication between multiple and multiple people. Third, voluntary activities are carried out following the prior posting and the comments about an event. Fourth, there is a possible side effect that those activities can increase the fear of crime and the distrust among residents. The municipal police needs to seek an appropriate model for crime prevention activities involving residents in consideration of the characteristics of social media. First of all, it is necessary to provide guidelines so that residents can conveniently create a new activity group. Also, nudge-type intervention can be considred, such as providing information on new crimes and inducing discussions on local pending issues. Finally, it is necessary to work with existing residents communities that pursue other purposes.