| John McGillen | |
| Position: | Pitcher |
| Bats: | Right |
| Throws: | Left |
| Birth Date: | August 6, 1917 |
| Birth Place: | Eddystone, Pennsylvania, U.S. |
| Death Place: | Upland, Pennsylvania, U.S. |
| Debutleague: | MLB |
| Debutdate: | April 20 |
| Debutyear: | 1944 |
| Debutteam: | Philadelphia Athletics |
| Finalleague: | MLB |
| Finaldate: | April 29 |
| Finalyear: | 1944 |
| Finalteam: | Philadelphia Athletics |
| Statleague: | MLB |
| Stat1label: | Win–loss record |
| Stat1value: | 0–0 |
| Stat3label: | Strikeouts |
| Stat3value: | 0 |
| Stat2label: | Earned run average |
| Stat2value: | 18.00 |
| Teams: | |
John Joseph McGillen (August 6, 1917 – August 11, 1987) was an American professional baseball pitcher. He appeared in two games in Major League Baseball for the Philadelphia Athletics during the 1944 season.