John Richard Markell (born March 10, 1956) is a Canadian ice hockey coach and former professional player. Markell played 55 games in the National Hockey League and later coached Ohio State University.

Born in Cornwall, Ontario, Markell attended Bowling Green State University, where he was a four-year letter winner and served as an assistant captain as a senior on the Falcon hockey team that went 37-6-2. He was BG's leading scorer as a junior with 61 points after leading the team in goals as a sophomore with 26. Markell finished his career with 235 points, including 102 career goals. He also had 133 career assists. Markell was voted BG's outstanding forward in 1978 and 1979. After going undrafted, Markell played 55 National Hockey League games: 52 with the Winnipeg Jets, two with the St. Louis Blues and one with the Minnesota North Stars. In his NHL career, Markell scored 11 goals and 10 assists.

Markell served as the head coach of the Ohio State University ice hockey team from 1995 until the end of the 2009-10 season. The seventh Buckeye head coach, he led the team to the NCAA tournament six times, marking the only appearances in program history, with an NCAA Frozen Four appearance in 1998.