Janice "Jan" Melbourne Merrill (born June 18, 1956) is a retired American runner. She was the dominant long-distance runner of the middle 1970s, a notable front runner, her uniform with the large "M" on her chest would usually break away to an insurmountable lead in domestic meets. She was equally untouchable in self-promotion or dealing with the media, often deferring to her coach, Norm Higgins. At various points in time she held the American record in the 1500 meters (4:02.61 set on July 29, 1976) during the 1976 Summer Olympics in Montreal, the 3,000 meters and 5,000 meters. She lost other record opportunities because the only times she could get a decent race in the United States was against men.

She won the U.S. title at 1500 meters twice outdoors, 3000 meters 4 times, twice in the indoor mile, twice in the indoor 2 mile and twice in Cross Country. After retiring from competitions she became a high school and college track coach.