Magnetic field effects on the thermoelectric power of MnP single crystal in the metamagnetic state are studied for various directions of the thermal current flow and magnetic field in the temperature range from 7.15°K to 45°K. Abrupt changes of the thermoelectric power are observed when the screw state transforms to the ferromagnetic state or the fan state by the magnetic field. Main features of the obtained results are consistent with those of the resistivity measurements reported in the preceding paper, except for the results with the magnetic field applied along the b axis. On the basis of the model proposed in the preceding paper we discuss the obtained results in connection with the delicate variation of the electron and hole pockets under the external field. © 1969, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.