The success of User Generated Content Virtual Communities (UGCC) greatly depends on the voluntary participation and continued contribution of their members. Therefore, more and more community operators and companies reward contributors, but there is not well understood: Do incentives will diminish intrinsic motivation of participation? Our study contributes to classify the incentive policies to monetary and non-monetary incentive, and how they influence the motivation of participation. Drawing on theories of SDT, we develop a theoretical model relating the motivations, participation, and performance of community participants. Our results reveal several important ?ndings. First, the monetary incentive will diminish the intrinsic motive while have different influence on the two internal motives (reputation, own-use value); Second, non-monetary incentive has the same positive influence on both intrinsic and internal motives. Third, the intrinsic motive and internal motives have impact on participation behavior in different ways, the other-oriented motives (reputation, altruism) have the significant positive influence, while the self-oriented motives (the enjoyment, own-use) have the significant negative impact on participation. The study shows that monetary incentive has more crowding effect while non-monetary incentive exhibits more reinforcing effect in the UGCC. Lastly, the theoretical contribution and managerial implication were concluded.