Reference points (M1 through M17) are specified in colors at two or more positions longitudinally spaced at a given interval on a golf club shaft (11a) and one or more positions selected from among a golfer's head and the like. A moving image of a golfer's swing is photographed by cameras (13-1, 13-2). The moving image of the swing is converted into a plurality of still images. The still images are stored in a computer (14). Evaluation items to be checked including a swing posture and a shaft angle in a range from an addressing state till an impact state are expressed by numeric values, based on coordinate data of each of the reference points (M1 through M17) disposed on a plurality of the still images. The data expressed by the numeric values are compared with judging data inputted to the computer (14) in advance as ideal values.