An image sensing apparatus has a plurality of pixels arranged two dimensionally, each pixel containing a photoelectric converter that outputs a photoelectrically converted signal in response to a quantity of received light, an output unit containing a clamping circuit, a signal supply circuit that outputs a reference signal to the clamping circuit, a control unit that controls to clamp the reference signal prior to outputting the photoelectrically converted signal from the pixel to the clamping circuit, output the photoelectrically converted signal to the clamping circuit, and then output a noise signal from the pixel to the clamping circuit, and a differential circuit that subtracts the noise signal from the photoelectrically converted signal processed by the clamping circuit.