The Cleveland Monsters began in 1994, as the Denver Grizzlies. They lasted only a single season before becoming the Utah Grizzlies until 2005. In 2006 they relaunched as the Lake Erie Monsters, relocating to Cleveland, Ohio, to replace the Cleveland Barons, who had been relocated to Massachusetts the previous season. They began play in the 2007-08 season as the AHL affiliate of the Colorado Avalanche.
In the 2015-16 season, the Lake Erie Monsters began a new life as the AHL affiliate of the Columbus Blue Jackets. They would start the agreement strong, finishing the regular season with a franchise record in points and a Calder Cup victory. After that victory, the Lake Erie Monsters rebranded to the Cleveland Monsters.
In the 2018-19 season, they moved from the Central Division to the North Division, where they continue to play. They briefly moved back in the 2020-21 season, due to the COVID-19 pandemic and the temporary formation of the All-Canada Division, but they returned to the North Division in the 2021-22 season.
The Monsters have only one Calder Cup, defeating the Hershey Bears in a Finals sweep in 2016. It remains their best season in franchise history.
In the 2022-23 season, the Monsters finished with a record of 33-32-5-2, sixth in the North Division. They missed out on the Calder Cup playoffs by three points.
Their current head coach is Trent Vogelhuber, their current GM is Chris Clark, and they play out of Rocket Mortgage Fieldhouse.
Notable former Monsters include Zach Werenski, Cam Atkinson and Oliver Bjorkstrand.