Abstract: The topology optimization of power collection in offshore wind farms is a large-scale non-convex and nonlinear optimization problem, for which it is difficult to obtain the optimal solution. It is therefore divided into two parts: internal topology optimization and feeder path optimization. Inside the partition, the optimal topology mode is obtained by taking economy as the objective function with consideration of submarine cable selection. In the feeder part, aiming at the submarine cable crossing problem, a partition regularization scheme is proposed with consideration of the actual construction engineering constraints of the wind turbines. By using the improved Dijkstra algorithm, the transition from the traditional line-line intersection judgment to the line-surface intersection judgment is realized, and the situation that the crossover experiment cannot judge the submarine cable crossing is avoided. Finally, a case study of two offshore wind farms is studied and the proposed algorithm is compared with other topological results, which has proved the feasibility and superiority of the proposed algorithm.