Pinnau (disambiguation)
Pinnau denotes:
- the river Pinnau in the district of Pinneberg
 - a stream in the Möllner Seenplatte
 - a district of the municipality of Amt Neuhaus in the district of Lüneburg
 - German name of Piniewo in Gmina Pasłęk in Poland, Warmian-Masurian Voivodeship
 - a former estate near Brandenburg in East Prussia (today Selenowo )
 
Pinnau is the family name of the following people:
- Caesar Pinnau (1906–1988), German architect
 - Ruth Pinnau († 2010), German author, wife of Caesar Pinnau