In this paper, we measured movement of horse's hip top and displacement of various part of the rider. Jar (up and down motion) during trotting was measured, relation to the rider's motion. The judge's evaluation was clarified with the amount of displacement of the horse. First, the general rider has the heel in a position that is lower than the junior rider. This showed that sticking of jockey's leg and horse's body was good. Next, an advanced score concerning the comprehensive evaluation of the screening criterion lowers when the movement of horse's hips in the top part is small. This showed becoming the demerit mark by each movement subject.