In the process of inspection for the electricity transmission equipment using flying robots, an automatic way to find the best viewpoint to get the high quality of image would be beneficial to observe the state of the electricity transmission equipment. Finding the best viewpoint belongs to the viewpoint selection problem. A strategy is proposed in this paper to find the best viewpoint for the electricity transmission equipment inspection, according to which the candidate viewpoints can be generated based on the 3D model of the equipment. Then a scoring function is constructed which combines three factors including the amount of the information, the viewing quality, and the visibility of the information to evaluate the quality of the candidate viewpoint. Finally, the best viewpoint can be selected from all of candidate viewpoints according to the scoring function. The proposed algorithm is tested on the experiment to demonstrate its effectiveness.