| Competition: | National Soccer League |
| Season: | 1978 |
| Dates: | 5 March — 17 September 1978 |
| Matches: | 182 |
| Total Goals: | 532 |
| League Topscorer: | Ken Boden Clive Eaton (14 goals each) |
| Best Goalkeeper: | Allan Maher (10 clean sheets) |
| Biggest Home Win: | (28 March 1978) South Melbourne 5–0 Adelaide City (13 August 1978) |
| Highest Scoring: | Marconi Fairfield 6–2 Western Suburbs (16 April 1978) |
| Longest Wins: | 8 matches West Adelaide |
| Longest Unbeaten: | 13 matches Marconi Fairfield |
| Longest Winless: | 15 matches Canberra City |
| Longest Losses: | 7 matches Brisbane City |
| Highest Attendance: | 18,000 South Melbourne 1–1 Fitzroy United (2 April 1978) |
| Lowest Attendance: | 330 Brisbane Lions 1–1 South Melbourne (26 March 1978) |
| Prevseason: | 1977 |
| Nextseason: | 1979 |
The 1978 National Soccer League was the second season of the National Soccer League, the former top-tier Australian soccer league, since its establishment in 1977. The premiers were West Adelaide.
Note: Table lists in alphabetical order.
The top four teams in the league entered a playoff series, however the winner of the grand final match was not considered the overall winner of the NSL season, unlike other NSL grand finals.[1]