A composite gear and method of making same. In one embodiment the gear includes a body portion having a plurality of teeth. The gear is formed by placing it in a suitable tool such that a compressive stress is exerted on the teeth adjacent the root portion of each tooth. A portion of the gear adjacent the teeth is wrapped with a resin fibrous material that is allowed to cure while the compressive stress is maintained on the gear. When the resin fibrous material has at least substantially cured and the gear is removed from the tool, a permanent compressive stress is formed at the root portion adjacent each tooth. The compressive stress counteracts the tension stress that is experienced at the root portions of the teeth when the gear is in use, thus significantly strengthening (i.e., toughening) the gear and increasing its fatigue life.