A surgical instrument includes: a handpiece; a movable member configured to transmit a driving force to a treating member to treat a subject by moving relatively to the handpiece; and a connector arranged inside the handpiece, and including a strip to apply a pressing force to the movable member. The movable member includes a first conductive portion formed therein. The connector includes a second conductive portion formed on the strip. The second conductive portion abutting against the first conductive portion to connect the movable member and the handpiece electrically. The second conductive portion of the connector is a molded interconnect device constituting a three-dimensional circuit.