| Mase Graffen | |
| Position: | Manager |
| Bats: | Unknown |
| Throws: | Unknown |
| Birth Date: | c. 1845 |
| Birth Place: | Philadelphia, Pennsylvania |
| Death Place: | Silver City, New Mexico |
| Debutleague: | MLB |
| Debutdate: | April 25 |
| Debutyear: | 1876 |
| Debutteam: | St. Louis Brown Stockings |
| Finalleague: | MLB |
| Finaldate: | September 9 |
| Finalyear: | 1876 |
| Finalteam: | St. Louis Brown Stockings |
| Statleague: | MLB |
| Stat1label: | Games |
| Stat1value: | 56 |
| Stat2label: | Win–loss record |
| Stat2value: | 39 - 17 |
| Stat3label: | Winning % |
| Stat3value: | .696 |
| Teams: | |
Samuel Mason Graffen (c. 1845 - November 18, 1883) was a manager in Major League Baseball. He managed the St. Louis Brown Stockings of the National League for part of the 1876 season.
His career managerial record was 39-17 in 56 games.