Abstract: According to an apparatus for and a method of improving rotation stability and expandability of an integrated scanning system provided in the present invention, an intravascular photoacoustic scanning system is provided with a slip ring and an optical rotary joint disposed independently on the same shaft, and an intermediate shaft disposed with the slip ring and the optical rotary joint in parallel to transfer torque of a motor, whereby it is possible to expand a configuration of the system with an additional component, and to obtain stable rotation by independent drive control for power transfer of components such as the slip ring and the optical rotary joint.