An image pickup apparatus includes an optical system which includes a plurality of lenses, and an image sensor which is disposed at an image position of the optical system, wherein the optical system includes in order from an object side, a first lens having a negative refractive power, a second lens having a negative refractive power, a third lens having a positive refractive power, and a fourth lens, and the following conditional expressions (1) and (2) are satisfied:α max−α min<4.0×10−5/° C. (1), and0.1
