The 1990–91 Divizia B was the 51st season of the second tier of the Romanian football league system.
The format has been maintained to three series, each of them having 18 teams.
Victoria București and FC Olt Scornicești were excluded due to fall of communism in December 1989.
This decision was made after it was proved that the ascension of the two teams was a forced one, with the help of the communist regime.
Victoria was sponsored by the Romanian Ministry of Internal Affairs (the "Miliția", Police) and FC Olt was based in the hometown of Nicolae Ceaușescu, the former general secretary of the Romanian Communist Party from 1965 to 1989.