Purpose: The purpose of the study was to compare differences of firing sequences for beginning and peak values of EMG signals among three different target distances of over-arm throwing. Method: Ten subjects who were asked to throw to the target from three different distances (10m, 15m, 20m) voluntarily participated in this study. In order to obtain athlete performances, present study used high speed camera (Mega Speed MS10K CCD B/W, 100Hz) and adapted EMG measurement system (Mega ME3000P8, 1000 Hz) to collect data simultaneously. The study adapted the dependent One-way ANOVA (α=.05) to compare the differences among three different target distances of over-arm throwing. Results: The results indicated that firing sequences of beginning for the biceps brachii muscle, trapezius muscle and latissimus dorsi muscle of 20m were earlier than those of 10m significantly. The firing sequences of beginning were changed by different target distances. These muscles that started firing earlier were extensor carpi radialis muscle and trapezius muscle. The firing sequences of beginning for latissimus dorsi muscle were moving ahead as the target distance increased. The firing sequences of peak values for upper extremities muscles were also changed by the different target distances. But the firing timing of peak values among three target distances weren’t different significantly. The firing timing of peak values for the trapezius muscle, biceps brachii muscle and deltoid muscle were shown earlier than those of the others. Conclusion: It was concluded that firing sequences of beginning and peak values of upper extremities muscles for 20m target distance were better than those of the others'. Because the process of energy transfer for 20m target distance which was from the hip, shoulder joint and elbow joints and then to the wrist joint matched the principle of the kinetic chain.