An object detection apparatus includes a fusion target generation section that generates a fusion target by combining first target information, which is acquired as a reflected wave of a carrier wave, of an object present ahead of an own vehicle and second target information, which is acquired by image processing by an imaging unit, of the object present ahead of the own vehicle, and that detects the object by using the fusion target. The apparatus includes a first lateral position acquisition means that acquires a first lateral position indicating a position of the object with respect to a width direction of the own vehicle by using the fusion target, a second lateral position acquisition means that acquires a second lateral position indicating a position of the object with respect to the width direction of the own vehicle by using the second target information, and a lateral position selection means that selects, as a lateral position of the object, the lateral position closest to the own vehicle between the first lateral position and the second lateral position.