A medical manipulator comprising a distal end side and a proximal end side configured to be attachable to or detachable from each other, comprising: a distal unit including, an end effector on the distal end side, a joint assembly (373, 377) located on a proximal end side of the end effector, and a first power transmission assembly (303, 304) for transmission in a longitudinal direction of a linear motion force for actuation of the end effector or the joint assembly (373, 377); a proximal unit including, a driver on the proximal end side for generating power for actuating the end effector or the joint assembly (373, 377), and a second power transmission assembly (207, 208) for transmission of power generated from the driver to the distal end side, and detachably mounted on the distal unit at a distal end; wherein the distal unit includes a first linear motion force conversion mechanism (301, 302, 327) linked to the first power transmission assembly (303, 304) to convert power from the second power transmission assembly (207, 208) to a linear motion force upon attachment of the distal unit to the proximal unit, characterized in that the first linear motion force conversion mechanism (301, 302, 327) includes a seesaw member that is rotatable about a rotating shaft, and has a contact portion coming in contact with the second power transmission assembly (207, 208) upon attachment of the distal unit to the proximal unit, wherein the seesaw member is connected to the first power transmission assembly (303, 304), and as a result of rotation of the seesaw member by power transmitted from the second power transmission assembly (207, 208), the first power transmission assembly (303, 304) is pushed or pulled in the longitudinal direction. a distal unit including, an end effector on the distal end side, a joint assembly (373, 377) located on a proximal end side of the end effector, and a first power transmission assembly (303, 304) for transmission in a longitudinal direction of a linear motion force for actuation of the end effector or the joint assembly (373, 377); a proximal unit including, a driver on the proximal end side for generating power for actuating the end effector or the joint assembly (373, 377), and a second power transmission assembly (207, 208) for transmission of power generated from the driver to the distal end side, and detachably mounted on the distal unit at a distal end; wherein the distal unit includes a first linear motion force conversion mechanism (301, 302, 327) linked to the first power transmission assembly (303, 304) to convert power from the second power transmission assembly (207, 208) to a linear motion force upon attachment of the distal unit to the proximal unit, characterized in that the first linear motion force conversion mechanism (301, 302, 327) includes a seesaw member that is rotatable about a rotating shaft, and has a contact portion coming in contact with the second power transmission assembly (207, 208) upon attachment of the distal unit to the proximal unit, wherein the seesaw member is connected to the first power transmission assembly (303, 304), and as a result of rotation of the seesaw member by power transmitted from the second power transmission assembly (207, 208), the first power transmission assembly (303, 304) is pushed or pulled in the longitudinal direction.