A top end portion of a medical manipulator has a surgical device accessible to a diseased area of a patient. In the manipulator, a pair of rolling members opposing to each other is provided. One of the pair of the rolling members is rolled by a flexible wire relative to the other rolling members. A plate maintains a distance between rotation centers of the pair of the rolling members constant. A pair of gears are held coaxially with the pair of the rolling members respectively, and engaged with each other. A link rotates the gear on an opposite side to a surgical device.