The Croatian Second Football League (Croatian: Druga hrvatska nogometna liga or commonly Druga HNL or 2.HNL) is the second highest football league in Croatia. The league was formed in 1991 with the dissolution of the Yugoslav Second League and it is operated by the Croatian Football Federation.
Between the 2001–02 season and 2005–06 season, the league was split in two divisions, one being the Northern Croatian Second League and the other being the Southern Croatian Second League. Each of these two leagues comprised twelve teams playing under a system pretty much identical to the one in the Prva HNL. However, since the start of the 2006–07 season, the united Croatian Second League comprises sixteen teams from the entire country. Relegation from this division is into one of the regional divisions of the Treća HNL.