A medical manipulator system includes a guide instrument having a treatment tool channel, an insertion body inserted into the treatment tool channel, a power source unit attachable to and detachable from the insertion body, a guide rail having a first region corresponding to a state in which the joint part is located in the treatment tool channel and a second region corresponding to a state in which the joint part is exposed from the distal end of the treatment tool channel, and the guide rail guides the power source unit to advance and retract in a predetermined linear direction defined by the first region and the second region, and a regulating part interposed in a boundary between the first region and the second region and the regulating part regulates a movement of the insertion body from the second region toward the first region.
