Jacob Riley (born November 2, 1988) is a retired American long-distance runner. He placed second behind Galen Rupp at the 2020 United States Olympic Trials (marathon), securing a spot at the 2020 Tokyo Olympics (which were rescheduled to start July 2021 due to the COVID-19 pandemic). Riley finished the race in a personal best time of 2:10:02. Riley was the first American (and ninth overall finisher) in the 2019 Chicago marathon, in a time of 2:10:36.
Riley represents the Boulder Track Club where he is coached by Lee Troop. Previously, he ran for the Hansons-Brooks Original Distance Project. In the 2016 US Olympic Trials Marathon, Riley finished 15th in 02:18:31. Riley won the 2012 USATF Club Cross Country Championship, covering the 10k race in a time of 29:58.
In college, Riley competed for Stanford University, where he was an 8-time All-American. Riley placed third in the 10,000m at the 2010 NCAA Championship, in a time of 28:57.41.
Riley is from Bellingham, Washington, and resides in Boulder, Colorado.