A one-piece, self-locking, molded plastic staple useful as a tissue fixation device in surgical procedures. The staple has opposed, pointed, L-shaped legs secured to a horizontal bridging member. Each leg has an extension which is engaged by a locking bar extending between the extensions when the staple is closed by forcing the legs through a 90.degree. arc. The staples may be extruded or molded of absorbable or nonabsorbable polymeric materials.