The medical manipulator (20) including a base section (25) at which a support surface (28a) is formed, a movable part (36) movably supported on the support surface, when a reference direction (X) parallel to the support surface is defined, between a distal end position (PI), which is a distal end side in the reference direction with respect to the base section, and a proximal end position, which is a proximal end side in the reference direction, a positioning mechanism configured to position the movable part at the distal end position with respect to the base section, a holding section (37) movably supported in the reference direction with respect to the movable part and configured to detachably hold a proximal end portion of a treatment tool (D10) such that a longitudinal direction of the treatment tool having an elongated shape is substantially parallel to the reference direction, and a driving unit (40) configured to move the holding section in the reference direction with respect to the movable part.