To thoroughly evaluate power flows of the transmission section with UHVAC/DC integration, and thus appropriately plan the power grid structure, a comprehensive evaluation method of power flow based on the analytic hierarchy process and the fan-shaped radar chart method is proposed. First, five independent indices in terms of system operation safety, economy and power flow distribution are selected during the comprehensive evaluation. The line-load rate, bus voltage and other indices are then optimized. Secondly, the fan-shaped radar chart method is used to assess the overall level and dispersion degree of the evaluation results, which can be employed to select optimal UHVAC/DC integration schemes. Finally, simulation verification is implemented via PSD-BPA. The results indicate that the method is helpful in improving the accuracy of power flow evaluation and the rationality of the evaluation results. This work is supported by National Natural Science Foundation of China (No. 51877084), Natural Science Foundation of Hebei Province (No. E2018502063), and Science and Technology Project of State Grid Corporation of China (No. SGHEJY00GHJS1900023).