The problem solved by the present invention is to provide a pinhole detection device with an improved accuracy of detecting pinholes. The detection unit of the pinhole detection device includes a plurality of optical fibers that transmit light that has passed through the object to be inspected. The plurality of optical fibers are arranged side by side while facing a light source. When a maximum detectable angle at which the pinhole with respect to an optical axis of the light source is detectable is defined as , a maximum angle of incidence of light that can be transmitted by the optical fiber with respect to the optical axis of the light source is set in a range of +0 to +5.