The 2003–04 Alpha Ethniki was the 68th season of the highest football league of Greece.
The season began on 23 August 2003 and ended on 22 May 2004.
Panathinaikos won their 19th Greek title and their first one in eight years.
Ergotelis were promoted to 2004–05 Alpha Ethniki.
Source: Galanis Sports Data Annual awards were announced on 9 November 2004.