An optical system is provided and includes a fixed module, a movable module, a driving coil, an electrical circuit and a magnetic element. The fixed module includes a base and a circuit board, and the movable module includes an optical member holder, configured to hold an optical member. The magnetic element corresponds to the driving coil and is configured to generate an electromagnetic driving force to drive the optical member holder to move relative to the base. The driving coil and the electrical circuit are integrally formed in the circuit board. The driving coil partially overlaps the electrical circuit when viewed along a direction perpendicular to an optical axis of the optical member.