A position control method, which positions the relative position of an optical disk and an optical pickup to a position that provides the optimum value of the jitter value of the detection signal obtained by detecting the reflected light of an optical spot, has a jitter value acquisition procedure, which carries out multiple feed operations within the adjustment range of the relative position and obtains the jitter value at each feed position, an edge position setting procedure which sets as the edge positions relative positions that exceed a prescribed preset jitter threshold value, an optimum position computation procedure, which computes the optimum position that yields the optimum value for the jitter value, and an edge position setting procedure that sets the edge positions on the condition that there are at least two relative positions that yield a jitter value that exceeds the jitter threshold value.