Semiconductor wafer placement position determination method and semiconductor epitaxial wafer production method

Provided is a semiconductor wafer placement position determination method making it possible to measure a position deviation at a placement position of a semiconductor wafer when using a susceptor that is N-fold symmetric with respect to the center of the susceptor as a rotation axis. In this method, an opening edge of a counterbore portion of the susceptor is N-fold symmetric with respect to the center of the susceptor as a rotation axis (N≥2). This method includes: a measurement step of measuring, while rotating the susceptor on which the semiconductor wafer is placed, a gap distance between a periphery of the semiconductor wafer and the opening edge; a first calculation step of performing, based on variation of the gap distance, period regression analysis; and a second calculation step of determining the position deviation based on an amplitude of a trigonometric function obtained by the first calculation step.