The purpose of this study was to clarify whether or not the center of gravity shifting to the non paralytic side in hemiplegics after stroke was influenced by relative distances of the voluntary shifted center of gravity from the paralytic side to the non-paralytic side and vice versa. Using 55 hemiplegics, bilateral points of the voluntary shifted center of gravity in a standing position were measured by means of the stabilometer for 10 seconds, each with the eyes open and closed, and also the voluntary shifting of the center of gravity to the non-paralytic side and the paralytic side. Mean of X-axis was employed as an index for the bilateral points of the center of gravity. The middle of the mean of X calculated from the center of gravity shifted between the non-paralytic side and the paralytic side was used as the middle point. A significant positive correlation between the spontaneous standing point and the middle point was obtained when the eyes were open and closed. The result suggests that the bilateral centers of gravity in the standing position of hemiplegics can be determined relatively by active shifted distances of the centers of gravity between the non-paralytic and paralytic sides.