Exploring the emergence and maintenance of cooperation in social dilemma is valuable and it arises considerable concs of many researchers.In this paper,we propose a mechanism to promote cooperation,called benefit community,in which cooperators linking together form a common benefit community and all their payoffs obtained from game are divided coequally.The robustness of conclusions is tested for the PDG (prisoners’ dilemma game) on square lattice and WS small world network.We find that cooperation can be promoted by this typical mechanism,especially,it can diffuse and prevail more easily and rapidly on the WS small world network than it on the square lattice,even if a big temptation to defect b.Our research provides a feasible direction to resolve the social dilemma.