Rosenau may refer to various places in Europe:
- in Austria:
- Rosenau am Hengstpaß, Upper Austria
- a hamlet near Seewalchen am Attersee, Upper Austria
- the boroughs Rosenau Markt and Rosenau Schloss in Zwettl, Lower Austria
- Schloss Rosenau, Zwettl, a castle near Zwettl
- in Germany:
- Rosenau, Brandenburg, in the district of Potsdam-Mittelmark, Brandenburg
- Schloss Rosenau, Coburg, a castle in Rödental, Bavaria
- a borough of Grafenau, Bavaria
- a borough of Engelskirchen, North Rhine-Westphalia
- a borough of Langenpreising, Bavaria
- Rosenau (Königsberg), a former quarter of Königsberg, Prussia
- in France:
- Rosenau, Haut-Rhin, a commune in the region of Grand Est
Rosenau is the German name of:
- Râşnov, Romania
- Rožnov pod Radhoštěm, Czech Republic
- Rožňava, Slovakia
- Zilupe, Latvia
- Jastrzębowo, Poland
Rosenau is the surname of:
- James N. Rosenau (1924–2011), American political scientist and international affairs scholar
- Milton J. Rosenau (1869–1946), American public health official and professor
- William Rosenau (1865-1943), Leader of Reform Judaism