Citizen science is an activity of the public participating in real scientific research projects through crowdsourcing. This Article concisely describes that citizen science is the effective measure to deal with the development trends of popularization of science in future China，introduces the practices of citizen science in USA，explained the various types of citizen science and basic principles of implementation of citizen science. This paper particularly analyzes the necessity and feasibility of carrying out projects of citizen science in Beijing-Tianjin-Hebei area，and puts forward some suggestions for taking the lead in carrying out projects of citizen science in this area.