| NBL champions | League champions | Runners-up | Finals berth |
| Season | Tier | League | Regular season | Post-season | Head coach | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Finish | Played | Wins | Losses | Win % | |||||||
| City of Sydney Astronauts | |||||||||||
| 1979 | 1 | NBL | 7th | 18 | 8 | 10 | .444 | Did not qualify | Charlie Ammit | ||
| 1980 | 1 | NBL | 10th | 22 | 7 | 15 | .318 | Did not qualify | Charlie Ammit | ||
| 1981 | 1 | NBL | 9th | 22 | 8 | 14 | .364 | Did not qualify | Charlie Ammit | ||
| Sydney Supersonics | |||||||||||
| 1982 | 1 | NBL | 12th | 26 | 7 | 19 | .269 | Did not qualify | Charlie Ammit | ||
| 1983 | 1 | NBL | 1st | 22 | 19 | 3 | .864 | Eliminated round robin 1–2 | Owen Wells | ||
| 1984 | 1 | NBL | 9th | 24 | 3 | 21 | .125 | Did not qualify | Owen Wells | ||
| 1985 | 1 | NBL | 11th | 26 | 9 | 17 | .346 | Did not qualify | Paul Coughter | ||
| 1986 | 1 | NBL | 6th | 26 | 14 | 12 | .538 | Lost elimination final (Brisbane) 82–100 | Owen Wells | ||
| 1987 | 1 | NBL | 10th | 26 | 9 | 17 | .346 | Did not qualify | Ken Cole | ||
| Regular season record | 212 | 84 | 128 | .396 | 1 regular season champions | ||||||
| Finals record | 4 | 1 | 3 | .250 | 0 NBL championships | ||||||
As of the end of the 1987 season
*Note: In 1983 and 1984, the NBL was split into Eastern and Western divisions during the regular season.
Source: Sydney Supersonics Year by Year