As one of the main modes of capacity sharing in the shipping alliance, the essence of which is the space mutual rent transaction among members. However, under the current trading system, the sharing of capacity between shipping enterprises requires a lot of transaction costs and communication costs, cooperation efficiency is not high, and there is a certain competitive relationship between enterprises, they work for their own interests, resulting in more difficult cooperation, and blockchain consensus mechanism, intelligent contracts, distributed bookkeeping and other characteristics can solve these problems of alliance cooperation. Therefore, based on the idea of blockchain, this paper designs a model of mutual lease cooperation in shipping union cabins, gives the model and process of mutual lease transactions based on blockchain, realizes mutual trust and win-win situation among members, simulates through the combination of Hyperledger Fabric and Matlab, and verifies the applicability of blockchain to shipping alliance capacity sharing cooperation.