| Harry Thompson | |
| Position: | Pitcher |
| Bats: | Left |
| Throws: | Left |
| Birth Date: | 9 September 1889 |
| Birth Place: | Nanticoke, Pennsylvania, U.S. |
| Death Place: | Reno, Nevada, U.S. |
| Debutleague: | MLB |
| Debutdate: | April 24 |
| Debutyear: | 1919 |
| Debutteam: | Washington Senators |
| Finalleague: | MLB |
| Finaldate: | June 28 |
| Finalyear: | 1919 |
| Finalteam: | Philadelphia Athletics |
| Statleague: | MLB |
| Stat1label: | Win–loss record |
| Stat1value: | 0–4 |
| Stat2label: | Earned run average |
| Stat2value: | 4.23 |
| Stat3label: | Strikeouts |
| Stat3value: | 11 |
| Teams: | |
Harold Thompson (September 9, 1889 – February 14, 1951) was an American Major League Baseball pitcher who played in with the Washington Senators and the Philadelphia Athletics.