Poznań Voivodeship (Polish: Województwo Poznańskie) was a unit of administrative division and local government in Poland in the years 1919–1939, created after World War I from the Prussian-German province of Poznań (Province of Posen).

During World War II, it was occupied by Nazi Germany and annexed as Reichsgau Wartheland "(Reich province of the Land of the Warta River)".

per 100 km2 (total length of railroads within the Voivodeship's area was 2684 km, the highest in the whole country).

With numerous cities and well-developed rail, it also was a breadbasket of the country, its highly efficient agriculture was well-mechanized.

The city of Poznań was a big industrial center, as well as a key railroad junction.