The Austrian Northwestern Railway (German: Österreichische Nordwestbahn, ÖNWB, Czech: Rakouská severozápadní dráha) was the name of a former railway company during the time of the Austro-Hungarian monarchy. Today, the term is still used (although only rarely) to refer to the railway line which was formerly operated by that company.
The privately owned Nordwestbahn took over the branch of the Nordbahn from Floridsdorf to in 1841 and extended it in 1871 via Hollabrunn and Retz to Znojmo (Moravia). Nordwestbahn owned and operated many important lines in Bohemia and Moravia. It was nationalized in 1908 and subsequently lost its significance. Vienna Northwest Station was closed down in 1924 and has only been used for freight transports since World War II. The bridge used by the company was transformed into an Autobahn bridge during the 60s. Passenger service between Retz and Znojmo was reopened in 1990.