A graduate of Southwest Missouri State University, Berry's coaching career began as an assistant at Fort Scott Community Junior College in Fort Scott, Kansas. In 1964 he moved to Sterling College, where he remained until March 1966 when he accepted the head coaching job at Fort Scott Community Junior College. Berry's tenure as FSCJC's head coached ended before he coached a single game when three months later he resigned to join the coaching staff at Southwest Missouri State.
From 1969 to 1970, Berry was the head coach at Missouri Southern State University, where he had an overall record of 4–15–1. After leaving MSSU, Berry served as the head coach at Northeastern Oklahoma A&M College and as the defensive line coach for the BC Lions.
On August 21, 1983, Berry replaced Joe Faragalli as head coach of the Saskatchewan Roughriders after a 1–5 start. The Roughriders finished last in the West Division in each of Berry's two seasons as head coach and on November 8, 1984 Berry was fired by the Roughriders.
Rueben Berry died of cancer in March 1998.
Head coaching record
|Sterling Warriors (Kansas Collegiate Athletic Conference) (1964–1965)|
|Missouri Southern Lions (Independent) (1969–1970)|
|National championship Conference title Conference division title|
|Team||Year||Regular Season||Post Season|
|Won||Lost||Ties||Win %||Finish||Won||Lost||Win %||Result|
|SSK||1983||4||6||0||.400||5th in West||-||-||-||-|
|SSK||1984||6||9||1||.406||4th in West||-||-||-||-|
- "Football Media Guide" (PDF). Sterling Warriors. Retrieved March 19, 2013.
- "Berry Resigns Here: Goes to Springfield". The Fort Scott Tribune. June 15, 1966. Retrieved 2010-08-10.
- "Missouri Southern State University Football Media Guide" (PDF). Missouri Southern State University.
- "SPORTS PEOPLE; Comings and Goings". The New York Times. August 21, 1983. Retrieved 2010-08-10.
- "Roughriders give Berry, Herrera axe". The Montreal Gazette. November 9, 1984. Retrieved 2010-08-10.
- Ziehm, Len (October 6, 1998). "Illinois State is facing one oddity after another". Chicago Sun-Times.