The 1939–40 Divizia B was the sixth season of the second tier of the Romanian football league system. The format has been maintained, four series of 10 teams. The winners of the series were supposed to promote in the Divizia A, but the winners of the 3rd and 4th series were not promoted from different reasons. Also 3rd and 4th place from the first series and the sixth place from the second series were promoted to fill the vacant places from Divizia A.