A medical instrument according to the present disclosure includes: a contact portion configured to contact body tissue; a drive unit configured to generate drive force for causing the contact portion to contact the body tissue; and a limiter mechanism configured to impose restriction on transmission of the drive force to the contact portion, in accordance with contact force of the contact portion with respect to the body tissue. This configuration makes it possible to restrict force applied to body tissue during surgery, and to reduce failure risk, with a simple configuration.