The non-cooperative decentralized system is modeled in the context of assembly system and vendor-managed inventory, and its inefficiency is discovered. Therefore, two revenue sharing mechanisms are proposed respectively under decentralized and cooperative decision modes. It is shown that both mechanisms can maximize the system efficiency. Given the profits of the players are equal in different mechanisms, the bargaining power spaces in different mechanisms exhibit similar characteristics under certain condition. Unfair distribution of revenue may arise in the first mechanism but can be avoided in the second one.