Although the cultivation of edible mushrooms has developed rapidly, there are still many problems. The instability of the supply chain and the uneven distribution of benefits have restricted the development of the mushrooms industry. In order to solve this problem, default risk, operating cost, willingness to cooperate, and information symmetry introduced as correction factors for a modified Shapley value, which fills up the shortcomings of the classic Shapley value. The profit distribution model of the supply chain gives a relatively reasonable profit distribution. The results show that: (1) Under decentralized decision-making, the benefits allocation is unreasonable, farmers have low bargaining ability and negative to planting. (2) Farmers in edible mushrooms supply chain are improved through classic Shapley value benefits allocation, while processors not motivated to participate in cooperation. (3) Pareto improvement be achieved under the optimal strategy of benefits distribution of edible mushrooms supply chain based on the modified Shapley value and "farmer + processors + supermarkets" alliance is stable.