The Dutch Tweede Divisie in the 1956–57 season was contested by 30 teams, divided in two groups.
RBC and Leeuwarden won the championship and were promoted to the Eerste Divisie.
The composition of the league was based on the results of the previous season.
The teams that had finished lowest in the Dutch amateur Eerste Klasse would play in this new league.
Teams that finished higher, would start in the Eerste Divisie.