Abstract: The connection of transmission system with multiple offshore wind farms and the land can achieve better coordination docking between offshore wind farm and the mainland power grid. The topology of the transmission network is one of the key issues. Because the booster station has a plurality of outlets and the position of booster stations and control center are uncertain, the shortest length of AC submarine cable is taken as the optimization objective. Firstly, DFS (depth-first search) and the shortest path methods are used to form the initial scheme. Then,the topology is optimized by using improved genetic algorithm based on Dijkstra algorithm. Finally,the simulation results show that the algorithm can generate the optimal economy topology scheme for transmission network with multiple wind farms automatically, which can save time and manpower. Meanwhile, it can provide an effective optimization method for automatic generation of cluster network topologies with multiple wind farms in the future, which is significant for the practical engineering application.