The purpose of this study is to examine the effect of giving an immediate feedback to a sprinter. In the experiment we will use photoelectric cell, which makes it possible to analyze a performance of a subject immediately with speed curve line data. The method of the experiment is as follows. The subject makes two consecutive 100m sprint. In a few minutes after the first dash, w hen his own running image is still on his head clearly, we give him quick advice based on the data. Then he makes second sprint and we examine how his performance has changed compared to his first sprint .A s a result, each nine subject marked better record with his running form improved. It suggests that a sprinter is highly motivated when his performance data is fed back to him immediately. This experiment is considered to be a big help not only for the scientific but also for the practical approach to the field of sprint training.