An image pickup apparatus includes an image sensor including a plurality of normal pixels and OB pixels obtained by dividing each pixel into n, and an image processing circuit. The image sensor can read each pixel row in a first read mode in which a pixel signal is generated and read or in a second read mode in which n signals relating to n divided pixel signals are read in n rows. The image processing circuit performs processing on signals read in the first and second read modes to generate image data and performs OB level correction processing on a normal pixel signal read from the normal pixels in the second read mode using an OB pixel signal read from the OB pixels in the first and second read modes.