TARGET DETECTION DEVICE

A target detection device mounted in a vehicle includes: a radar specification unit; a same target determination unit; and an image specification unit that specifies, as image target position information, an image detection region of an image detection target detected on the basis of a captured image, the image detection region representing the position of the image detection target relative to the base point on an XY-plane with the X-axis representing the vehicle width direction of the vehicle and the Y-axis representing the vehicle length direction of the vehicle. The image specification unit sets the Y-axis range of the image detection region in the Y-axis direction on the basis of the bearing from the base point to each of the two X-directional ends of the image detection target in the captured image and of an expected width minimum value and an expected width maximum value in the X-axis direction.