| John Grogan | |
| Birth Date: | 24 September 1880 |
| Birth Place: | Streator, Illinois, U.S. |
| Death Place: | Wadena, Minnesota, U.S. |
| Player Sport1: | Football |
| Player Years2: | 1900–1903 |
| Player Team2: | Knox (IL) |
| Coach Sport1: | Football |
| Coach Years2: | 1904–1908 |
| Coach Team2: | Fargo College |
| Coach Years3: | 1909 |
| Coach Team3: | Idaho |
| Coach Sport4: | Basketball |
| Coach Years5: | 1908–1910 |
| Coach Team5: | Idaho |
| Coach Sport6: | Baseball |
| Coach Years7: | 1910 |
| Coach Team7: | Idaho |
| Overall Record: | 3–4 (football, Idaho only) 15–19 (basketball) 5–12 (baseball) |
John Sebastion Grogan (September 24, 1880 – October 22, 1952) was an American football, basketball, and baseball player and coach. He played college football at Knox College in Galesburg, Illinois from 1900 to 1903, where he dropkicked a 55-yard field goal in an upset win over the Illinois Fighting Illini.[1] Grogan served as the head football, basketball and baseball coach at the University of Idaho in Moscow, Idaho during the 1909–10 academic year.[2]