De Boston Marathon 1981 werd gelopen op maandag 20 april 1981. Het was de 85e editie van deze marathon.
De Japanner Toshihiko Seko zegevierde bij de mannen in 2:09.27. De Nieuw-Zeelandse Allison Roe won bij de vrouwen in 2:26.47.
In totaal finishten er 5590 marathonlopers, waarvan 5074 mannen en 516 vrouwen.
| rang | naam | land | tijd |
|---|---|---|---|
| Toshihiko Seko | 2:09.27 | ||
| Craig Virgin | 2:10.27 | ||
| Bill Rodgers | 2:10.35 | ||
| 4 | John Lodwick | 2:11.34 | |
| 5 | Malcolm East | 2:11.36 | |
| 6 | Jukka Toivola | 2:11.53 | |
| 7 | Dennis Rinde | 2:12.02 | |
| 8 | David Chettle | 2:12.24 | |
| 9 | Kyle Heffner | 2:12.32 | |
| 10 | Victor-Manuel Mora | 2:12.56 | |
| 11 | Greg Meyer | 2:13.08 | |
| 12 | Jouni Kortelainen | 2:13.15 | |
| 13 | Norman Wilson | 2:13.17 | |
| 14 | Walter Saeger | 2:13.31 | |
| 15 | Randy Thomas | 2:13.49 | |
| 16 | Louis Kenny | 2:13.52 | |
| 17 | Michael Pinocci | 2:14.10 | |
| 18 | Ralph Serna | 2:14.17 | |
| 19 | David Patterson | 2:14.19 | |
| 20 | Brian Maxwell | 2:14.58 | |
| 21 | Hilario Alvarez | 2:15.06 | |
| 22 | Robin Holland | 2:15.08 | |
| 23 | Neil Cusack | 2:15.21 | |
| 24 | David M Smith | 2:15.30 | |
| 25 | Rafael A Parra | 2:15.51 |
| rang | naam | land | tijd |
|---|---|---|---|
| Allison Roe | 2:26.47 | ||
| Patti Catalano | 2:27.52 | ||
| Joan Samuelson | 2:30.17 | ||
| 4 | Julie Shea | 2:30.55 | |
| 5 | Jacqueline Gareau | 2:31.27 | |
| 6 | Sissel Grottenberg | 2:33.03 | |
| 7 | Nancy Conz | 2:34.49 | |
| 8 | Laura Dewald | 2:35.57 | |
| 9 | Kiki Sweigart | 2:36.55 | |
| 10 | Lorrie Dierdorff | 2:38.04 | |
| 11 | Jane Wipf | 2:38.28 | |
| 12 | Laurie Binder | 2:39.36 | |
| 13 | Nanae Sasaki | 2:41.48 | |
| 14 | Janis Klecker | 2:41.50 | |
| 15 | Rosemary Longstaff | 2:43.03 | |
| 16 | Carol Cook | 2:43.09 | |
| 17 | Shirley Silsby | 2:45.00 | |
| 18 | Kitty Consolo | 2:45.09 | |
| 19 | Marilyn Hulak | 2:45.58 | |
| 20 | Julie Isphording | 2:46.41 | |
| 21 | Jean Kerr | 2:47.07 | |
| 22 | Jane Welzel | 2:48.27 | |
| 23 | Ford Madeira | 2:48.57 | |
| 24 | Sharon Given | 2:49.15 | |
| 25 | Susan Kainulainen | 2:49.25 |