In-situ conservation of wild relatives of crops has been one of the key issues of biological diversity conservation in the World and China in resent years. China has established 226 in-situ conservation sites of wild relatives of crops which distributed in 27 provinces and covered 51 species since 2001 with physical isolation and mainstreaming approaches. Among the total conserved sites, 154 sites with 39 species in 27 provinces and 72 sites with 31 species in 15 provinces were established with physical isolation approach and mainstreaming approach respectively. Based on the results from field surveys and analyses of the established in-situ conservation sites, the authors compared the advantages and disadvantages between physical isolation approach and mainstreaming approach, summarized the main experiences of both approaches and their facing problems, and provided some opinions and countermeasures on detected problems. Finally, some ideas on the main focuses and key points of in-situ conservation of wild relatives of crops in the future were discussed toward to the development trends in the area of biological diversity conservation in the World.