The medical manipulator including an arm formed in a tubular shape having a bending portion capable of bending, an insertion portion that is formed having channels, with the base end of the arm being connected to the distal end of the insertion portion so that lumens of the arm and the channels are in communication, an operation portion for operating the bending portion, and transmission members that connect the bending portion and the operation portion, wherein the operation portion includes an operation main body that supports the transmission members so as to being capable of freely advancing and retreacting in the direction in which each of the transmission members extend. A lever that has a tubular portion that allows insertion of the treatment tool, with one end side of the tubular portion being coupled to each of the transmission members via links, and the other end of the tubular portion capable of swinging about a rotation center that is established by the relative position with respect to the operation main body being fixed. A guide member that is fixed to the operation main body and coupled to the lever, and that guides the lever so that the turning angle about the rotation center at the other end of the lever is smaller than the turning angle about the rotation center at the one end.
