In a parking assistance method of a parking control device which executes parking control with respect to a free parking space surroundings a host vehicle, a first frame line of free parking space in a direction orthogonal to a vehicle width direction and a second frame line which forms a pair with the first frame line are detected, and a parking target is set on a straight line connecting between a point on the first frame line and a point on the second frame line, for example, the parking target is set on the straight line connecting between an end on the first frame line and an end on the second frame line, and parking control is executed so that a position of wheels of the host vehicle is matched with the parking target.