| 1981 NPB season | |
| League: | Nippon Professional Baseball |
| Sport: | Baseball |
| Season: | Regular Season |
| Mvp: | CL |
| Mvp Link: | Nippon Professional Baseball Most Valuable Player Award |
| Playoffs: | League Postseason |
| Conf1: | CL |
| Conf1 Link: | Central League |
| Conf1 Champ: | Yomiuri Giants |
| Conf1 Runner-Up: | Hiroshima Toyo Carp |
| Conf2: | PL |
| Conf2 Link: | Pacific League |
| Conf2 Champ: | Nippon-Ham Fighters |
| Conf2 Runner-Up: | Lotte Orions |
| Finals: | Japan Series |
| Finals Link: | 1981 Japan Series |
| Finals Champ: | Yomiuri Giants |
| Finals Runner-Up: | Nippon-Ham Fighters |
| Finals Mvp: | Takashi Nishimoto (YOM) |
| Finals Mvp Link: | Japan Series Most Valuable Player Award |
| Seasonslist: | List of Nippon Professional Baseball seasons |
| Seasonslistnames: | NPB |
| Prevseason Link: | 1980 Nippon Professional Baseball season |
| Prevseason Year: | 1980 |
| Nextseason Link: | 1982 Nippon Professional Baseball season |
| Nextseason Year: | 1982 |
The 1981 Nippon Professional Baseball season was the 32nd season of operation for the league.
| Central League[1] | G | W | L | T | Pct. | GB | |
|---|---|---|---|---|---|---|---|
| 130 | 73 | 48 | 9 | .603 | – | ||
| 130 | 67 | 54 | 9 | .554 | 6.0 | ||
| 130 | 67 | 58 | 5 | .536 | 8.0 | ||
| 130 | 56 | 58 | 16 | .491 | 13.5 | ||
| 130 | 58 | 65 | 7 | .472 | 16.0 | ||
| 130 | 42 | 80 | 8 | .344 | 31.5 |
| Pacific League[2] | G | W | L | T | Pct. | 1st Half Ranking | 2nd Half Ranking | |
|---|---|---|---|---|---|---|---|---|
| 130 | 68 | 54 | 8 | .557 | 4 | 1 | ||
| 130 | 68 | 58 | 4 | .540 | 3 | 2 | ||
| 130 | 63 | 57 | 10 | .525 | 1 | 3 | ||
| 130 | 61 | 61 | 8 | .500 | 2 | 5 | ||
| 130 | 53 | 65 | 12 | .449 | 5 | 6 | ||
| 130 | 54 | 72 | 4 | .429 | 6 | 4 |
The Pacific League teams with the best first and second-half records met in a best-of-five playoff series to determine the league representative in the Japan Series.
Nippon-Ham Fighters won the series 3–1–1.
| Game | Score | Date | Location | |
|---|---|---|---|---|
| 1 | Orions – 1, Fighters – 4 | October 7 | Kawasaki Stadium | |
| 2 | Orions – 5, Fighters – 5 | October 10 | Kawasaki Stadium | |
| 3 | Fighters – 4, Orions – 1 | October 11 | Korakuen Stadium | |
| 4 | Fighters – 6, Orions – 11 | October 12 | Korakuen Stadium | |
| 5 | Fighters – 8, Orions – 4 | October 13 | Korakuen Stadium |
See main article: 1981 Japan Series. Yomiuri Giants won the series 4–2.
| Game | Score | Date | Location | Attendance | |
|---|---|---|---|---|---|
| 1 | Fighters – 6, Giants – 5 | October 17 | Korakuen Stadium | 36,056[3] | |
| 2 | Fighters – 1, Giants – 2 | October 18 | Korakuen Stadium | 42,376 | |
| 3 | Giants – 2, Fighters – 3 | October 20 | Korakuen Stadium | 36,180 | |
| 4 | Giants – 8, Fighters – 2 | October 21 | Korakuen Stadium | 38,627 | |
| 5 | Giants – 9, Fighters – 0 | October 23 | Korakuen Stadium | 31,419 | |
| 6 | Fighters – 3, Giants – 6 | October 25 | Korakuen Stadium | 43,604 |