Donald S. Martinez (1903-1955), was an American commercial fly tier, fly shop owner and fly angler. He is most noted for his development and promotion of the woolly worm fly and dry fly fishing in the Yellowstone National Park region. He operated a seasonal fly shop in West Yellowstone, Montana during the summers of 1932-1943. Pat Barnes bought the business after World War II and operated the Pat Barnes Tackle Shop until 1981.