The use of UAV for 3D surface inspection has become an important tool in the field of large-scale structure maintenance. However, the commonly used UAV inspection path planning algorithms for 3D surface suffer from problems such as path quality dependent model accuracy, path inspection efficiency, and low inspection quality. To address these issues, this paper proposes a UAV 3D surface inspection path planning algorithm based on normal vector filtering and integrated viewpoint Evaluation. Generate a safe and effective set of viewpoints through uniform sampling and normal vector viewpoint filtering, and then use a integrated viewpoint evaluation method combined with Monte Carlo tree search to select viewpoints, thereby generating a safe, efficient, and complete UAV surface inspection path. The results of simulation and physical experiments show that the proposed method can effectively solve the path planning problem when using UAV for surface inspection of large three-dimensional structures. Meanwhile, while ensuring the quality of inspection, this method can reduce path redundancy and improve the surface inspection efficiency of UAV.