Provided is a locking plate system for treatment of a distal radius fracture, intended to improve cooperation between screw anchors made of metal and a plate made of resin as well as to enhance matching with respect to the radius. The radius locking plate (4) is a flat laminate of intermediate molding materials that each include carbon fibers as reinforcing material and thermoplastic resin as a matrix. The screw anchor (5) includes a shaft portion (10) which has a principal thread (13) achieving a self-tapping action formed thereon and an outer circumference of a head portion of the screw anchor (5) which has an auxiliary thread (13) achieving a self-tapping action tapped thereon. A diameter of a through-hole (6) in the radius locking plate (4), which allows the radius main body (3) and the fractured bone piece (2) to be threadably fixed to the radius locking plate (4), is oversized relative to the principal thread (11), and is undersized relative to the auxiliary thread (13).
