A lens apparatus is disclosed which allows a reduced overall length when it is put into a barrel body while a high magnification of taken images is realized. The lens apparatus includes a first holding member which holds a first lens unit; a second holding member which holds a second lens unit disposed closer to an image plane side than the first lens unit; a first cam member which has a first cam portion driving the first holding member in an optical axis direction; a second cam member which has a second cam portion driving the first cam member in the optical axis direction; and a third cam member which includes a third cam portion driving the second holding member in the optical axis direction.