| Biographical details | |
|---|---|
| Born | May 30, 1935 Sandusky, Ohio, U.S. |
| Died | May 25, 2018 (aged 82) Bloomington, Indiana, U.S. |
| Playing career | |
| 1955–1956 | Miami (OH) |
| Position(s) | End |
| Coaching career (HC unless noted) | |
| 1960–1964 | Bowling Green (assistant) |
| 1965 | Yale (assistant) |
| 1966–1968 | Ohio State (assistant) |
| 1969–1973 | Miami (OH) |
| 1974–1978 | Colorado |
| 1980–1983 | Northern Illinois |
| 1984–1996 | Indiana |
| Head coaching record | |
| Overall | 168–129–4 |
| Bowls | 4–6 |
| Accomplishments and honors | |
| Championships | |
| 2 MAC (1973, 1983) 1 Big Eight (1976) | |
| Awards | |
| 2× MAC Coach of the Year (1973, 1983) 2× Big Ten Coach of the Year (1986–1987) | |
William Guy Mallory (May 30, 1935 – May 25, 2018) was an American college football player and coach. He served as the head football coach at Miami University in Oxford, Ohio from 1969 to 1973, the University of Colorado at Boulder from 1974 to 1978, Northern Illinois University from 1980 to 1983, and Indiana University Bloomington from 1984 to 1996, compiling a career head coaching record of 168–129–4.