David Miles Grylls (born September 29, 1957) is a retired track cyclist from the United States. He represented his native country at the 1984 Summer Olympics in Los Angeles, California, where he won the silver medal in the men's 4000 m team pursuit, alongside Steve Hegg, Leonard Nitz, Patrick McDonough and Brent Emery. He now coaches junior cyclists at the San Diego Velodrome.