Provided are a vehicle open/close portion control apparatus and a vehicle open/close portion control method such that a seizure determination for an open/close portion can be made more accurately even with an extremely simple structure. The vehicle open/close portion control apparatus is provided with: a seizure determination device fitted to a motor for performing an open/close drive for a vehicle open/close portion to make a foreign object seizure determination based on a change in the rotational speed of the motor; and a demagnetization pulse application means that supplies the motor with reverse-polarity power at the end of the open/close drive in a pulsed manner.