A medical manipulator comprising: a first input unit that is operated by hands; a shaft that extends from a body in which the first input unit is provided; a tip operating unit that is provided at a tip of the shaft and includes an end effector to which an operation of the first input unit is mechanically transmitted and in which the operation is performed; and a detection mechanism (400, 420, 430, 430a, and 470) that detects an operation state of the first input unit, wherein the detection mechanism detects a position in an operation direction of the first input unit, and the tip operating unit includes a posture change mechanism that changes a posture of the end effector with respect to the shaft, wherein the medical manipulator further includes, an operating unit that includes a second input unit that is operated by hands, a grip handle that is gripped by hands, and a drive source that drives the posture change mechanism based on an operation of the second input unit, and a working unit that includes the tip operating unit, and the shaft and can be attached to and detached from the operating unit, a driving force of the drive source is mechanically transmitted to the posture change mechanism in a state where the working unit is mounted on the operating unit, thereby, a posture of the end effector is changed, characterized in that the working unit also includes the first input unit, the detection mechanism includes, a drive element that is operated along with the first input unit, a driven element that is provided in the operating unit and operates in conjunction with the drive element in the state where the working unit is mounted on the operating unit, and a detecting unit that detects a position of an operation direction of the driven element wherein the first input unit is a trigger lever that is operated to rotate, the drive element is a first gear portion that includes teeth which extend in a circumferential direction around a rotation axial center of the trigger lever, the driven element is a second gear portion that is rotatably provided in the operating unit and meshes with the first gear portion in the state where the working unit is mounted on the operating unit, and the detecting unit is a rotation detector that detects a rotation angle of the second gear portion. a first input unit that is operated by hands; a shaft that extends from a body in which the first input unit is provided; a tip operating unit that is provided at a tip of the shaft and includes an end effector to which an operation of the first input unit is mechanically transmitted and in which the operation is performed; and a detection mechanism (400, 420, 430, 430a, and 470) that detects an operation state of the first input unit, wherein the detection mechanism detects a position in an operation direction of the first input unit, and the tip operating unit includes a posture change mechanism that changes a posture of the end effector with respect to the shaft, wherein the medical manipulator further includes, an operating unit that includes a second input unit that is operated by hands, a grip handle that is gripped by hands, and a drive source that drives the posture change mechanism based on an operation of the second input unit, and a working unit that includes the tip operating unit, and the shaft and can be attached to and detached from the operating unit, a driving force of the drive source is mechanically transmitted to the posture change mechanism in a state where the working unit is mounted on the operating unit, thereby, a posture of the end effector is changed, characterized in that the working unit also includes the first input unit, the detection mechanism includes, a drive element that is operated along with the first input unit, a driven element that is provided in the operating unit and operates in conjunction with the drive element in the state where the working unit is mounted on the operating unit, and a detecting unit that detects a position of an operation direction of the driven element wherein the first input unit is a trigger lever that is operated to rotate, the drive element is a first gear portion that includes teeth which extend in a circumferential direction around a rotation axial center of the trigger lever, the driven element is a second gear portion that is rotatably provided in the operating unit and meshes with the first gear portion in the state where the working unit is mounted on the operating unit, and the detecting unit is a rotation detector that detects a rotation angle of the second gear portion.