An image pickup apparatus includes a receiver that receives, from an external apparatus, an instruction for changing a zoom position of a lens, a controller that performs control processing to change a zoom position of the lens based on a received instruction, and a determination unit that determines whether the external apparatus includes a function regarding zooming of the lens. When the determination unit determines that the external apparatus includes the function, the controller controls a zoom adapter, which performs a zoom setting of the lens and is attached to the lens, to change a zoom position of the lens based on a zoom setting notified by the external apparatus. When the determination unit determines that the external apparatus does not include the function, the controller controls the zoom adapter to change a zoom position of the lens based on a zoom setting performed in the zoom adapter.