Dinamo Zagreb were the defending champions, having won their eleventh championship title the previous season, and they defended the title again, after a win against Međimurje on 12 April 2008.
Kamen Ingrad were automatically relegated to Druga HNL as they finished last in the previous season, while Inter Zaprešić were automatically promoted from Druga HNL after winning the 2006–07 title.
During the first two rounds, each team played each other once home and away for a total of 22 matches.
Following the end of season, a home-and-away relegation/promotion play-off was contested between Inter Zaprešić (11th placed team in the First League) and Hrvatski Dragovoljac (2nd placed team in the 2007–08 Second Football League).
Matches were played on 17 and 21 May 2008, with Inter Zaprešić retaining their top level status by beating Hrvatski Dragovoljac 2–0 on aggregate.