A connector (1) for vertebra connection members (2) that connect a plurality of vertebrae via a rod (6) includes: a connector body (3) that has formed therein a rod orifice (14) into which the rod is inserted, a fixing member orifice (16) into which a fixing member (15) that fixes the rod inserted into the rod orifice is screwed, and a screw member orifice (13) into which a screw member (5) to be screwed into the vertebra is inserted, and that connects the rod and the screw member to be screwed into the vertebra; and a diameter adjusting member (4) that is inserted into the rod orifice and has formed therein a convex curved surface (21) that abuts against the rod orifice and a concave curved surface (22) that abuts against the rod. The screw member is inserted into the screw member orifice and fixed to the connector, and the rod is inserted into the rod orifice into which the diameter adjusting member has been inserted and is fixed to the connector.
