Provided is a side part structure of a vehicle capable of efficiently suppressing deformation of a rocker using a center pillar when the rocker begins to buckle due to a load transmitted from the center pillar to the rocker in the event of a side collision or the like, so that the deformation amount of the rocker may be decreased.The side part structure of the vehicle includes a center pillar 2 that extends in the vertical direction, and the lower end of the center pillar 2 is connected to a rocker 1 that extends in the longitudinal direction. A portion bonded to the rocker 1 in the center pillar 2 is provided with a front ridge line 24 and a rear ridge line 25 respectively located at the front and rear sides of the vehicle, and the front ridge line 24 and the rear ridge line 25 are both formed toward the center portion of the width direction of the center pillar 2 and become close to each other as they go downward.