| Maynard O'Brien | |
| Birth Date: | 12 January 1907 |
| Death Place: | Charleston, Illinois, U.S. |
| Alma Mater: | Illinois Wesleyan University University of Illinois at Urbana–Champaign |
| Coach Years1: | 1946–1950 |
| Coach Team1: | Eastern Illinois |
| Coach Years2: | 1952–1955 |
| Coach Team2: | Eastern Illinois |
| Overall Record: | 27–50–1 |
| Bowl Record: | 0–1 |
| Championships: | 1 IIAC (1948) |
Maynard "Pat" O'Brien (January 12, 1907 – March 16, 1990) was an American football coach. He was the 13th head football coach at Eastern Illinois State College—now known as Eastern Illinois University—in Charleston, Illinois, serving for nine seasons, from 1946 to 1950 and 1952 to 1955, and compiling a record of 27–50–1.[1]
O'Brien Field was named in Maynard O'Brien's honor.