A lens apparatus configured to be mountable on a camera body having an image sensor includes a first focus lens unit, a splitting optical unit disposed between the first focus lens unit and the image sensor, a second focus lens unit disposed between the splitting optical unit and the image sensor, the second focus lens unit being movable from an initial position along an optical axis to vary a focusing state, a focusing state detection unit configured to detect the focusing state using a light flux from the splitting optical unit, an actuator configured to drive the first focus lens unit, and a controller configured to control driving of the actuator according to an output from the focusing state detection unit. The controller stops driving of the actuator if the second focus lens unit is located at a position different from the initial position.