NSB Di 4 is a class of five diesel-electric locomotives built by Henschel for the Norwegian State Railways (NSB). Delivered in 1981, the class is used to haul passenger trains on the Nordland Line and are since 2001 the only revenue diesel locomotives used by NSB. The locomotives had electric components from Brown, Boveri & Cie and a 16-645E prime mover from Electro-Motive Division.