Pattensen (German: [ˈpatn̩zn̩] ⓘ) is a town in the district of Hanover, in Lower Saxony, Germany.

Pattensen is located in the historic landscape Calenberg Land between the Leine and the Deister hills.

The town of Pattensen has the following 8 boroughs (or Stadtteile), some of which were previously independent villages: Hüpede, Jeinsen, Koldingen, Oerie, Pattensen-Mitte, Reden, Schulenburg and Vardegötzen as well as the two hamlets Thiedenwiese und Lauenstadt.

von Hallermund built the Pattensen Castle to monitor the important trade routes that crossed the city in north–south and west–east directions.

The letter processing center for the greater Hanover area is located in Pattensen.