The 2009–10 Nemzeti Bajnokság I was the fifty-ninth series of the national team handball championship for Hungarian women.

1982 European Champions Cup winners, Vasas SC, ended a forty-two-year spell in the top division, having played in the Nemzeti Bajnokság I since 1967.

Despite ranking seventh in the last year's championship, Tajtavill-Nyíradony had to leave the competition, after they lost many of their sponsors and faced serious financial trouble.

The sides faced each other in a double round robin system and were given additional points according to their final position in the regular season.

Similar to the classification round for 9–12 places, clubs were rewarded with bonus points depending on their position in the regular season.

The top four teams of the regular season continued the battle for the title in a best-of-three playoff system, in which if a match ends with a draw, the winner is decided by penalty shootout.