| Administrator: | Test and County Cricket Board |
| Cricket Format: | Limited overs cricket(40 overs per innings) |
| Tournament Format: | League |
| Champions: | Warwickshire |
| Count: | 1 |
| Participants: | 17 |
| Matches: | 136 |
| Most Runs: | 693 Ken McEwan (Essex) |
| Most Wickets: | 27 Hallam Moseley (Somerset) |
| Previous Year: | 1979 |
| Previous Tournament: | 1979 John Player League |
| Next Year: | 1981 |
| Next Tournament: | 1981 John Player League |
The 1980 John Player League was the twelfth competing of what was generally known as the Sunday League. The competition was won for the first time by Warwickshire County Cricket Club.
| width=200 | Team | width=20 | Pld | width=20 | W | width=20 | T | width=20 | L | width=20 | N/R | width=20 | A | width=20 | Pts | width=60 | R/R |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Warwickshire (C) | 16 | 11 | 1 | 4 | 0 | 0 | 46 | 5.031 | |||||||||
| 16 | 11 | 0 | 5 | 0 | 0 | 44 | 4.744 | ||||||||||
| 16 | 10 | 0 | 5 | 0 | 1 | 42 | 4.849 | ||||||||||
| 16 | 9 | 0 | 6 | 0 | 1 | 38 | 4.504 | ||||||||||
| 16 | 8 | 0 | 6 | 0 | 2 | 36 | 4.111 | ||||||||||
| 16 | 8 | 0 | 7 | 0 | 1 | 34 | 4.134 | ||||||||||
| 16 | 8 | 0 | 7 | 0 | 1 | 34 | 3.960 | ||||||||||
| 16 | 8 | 0 | 7 | 1 | 0 | 34 | 4.718 | ||||||||||
| 16 | 6 | 0 | 6 | 2 | 2 | 32 | 5.042 | ||||||||||
| 16 | 7 | 0 | 8 | 1 | 0 | 30 | 4.427 | ||||||||||
| 16 | 6 | 0 | 8 | 1 | 1 | 28 | 4.589 | ||||||||||
| 16 | 6 | 1 | 8 | 0 | 1 | 28 | 4.452 | ||||||||||
| 16 | 6 | 0 | 9 | 1 | 0 | 26 | 4.300 | ||||||||||
| 16 | 6 | 0 | 10 | 0 | 0 | 24 | 4.936 | ||||||||||
| 16 | 6 | 0 | 10 | 0 | 0 | 24 | 4.441 | ||||||||||
| 16 | 6 | 0 | 10 | 0 | 0 | 24 | 4.576 | ||||||||||
| 16 | 4 | 0 | 10 | 0 | 2 | 20 | 4.605 | ||||||||||
| Team marked | |||||||||||||||||