The invention discloses a method for evaluating the swimming ability of fishes and application of the method in the fish passage facility design. The method comprises the steps that (1) fishes are selected as a target; (2) a test water channel is selected; (3) the sensing flow velocities of the fishes are tested, wherein the total length index, the body length index and the weight index of each fish are recorded, and temporary rearing continues; (4) the critical swimming speeds of the fishes are tested; (5) the onrush swimming speeds of the fishes are tested, wherein the total length index, the body length index and the weight index of each fish are recorded, and the onrush swimming speeds of the fishes are calculated; (6) repeated testing is carried out; (7) statistics is carried out on swimming speed test results, wherein the median of the sensing flow velocities, obtained through repeated testing, of the target fishes, the median of the critical swimming speeds, obtained through repeated testing, of the target fishes, and the median of the onrush swimming speeds, obtained through repeated testing, of the target fishes are calculated; (8) the range of the continuing swimming speeds, the range of durable swimming speeds and the range of the outburst swimming speeds are obtained in a short time, comprehensive evaluation is carried out on the swimming speeds of the fishes, and the maximum flow velocity of a main body structure, the fish luring flow velocity of an inlet, and the range of the flow velocities of an outlet in the fish passage facility design are determined.