An image sensor comprising: a pixel array in which a plurality of unit pixels are arranged in a matrix; a plurality of signal output lines provided for each column of the pixel array; a signal readout circuit provided for each column of the pixel array; and a control circuit for controlling a signal from the unit pixel of each column in a first row to be output to any of the signal output lines, and controlling the signal output to the any of the signal output lines to be input to the signal readout circuit. The control circuit controls, for each column, a signal from the unit pixel in a second row to be output to another of the signal lines while the signal output to the any of the signal output lines is being input to the signal readout circuit.