Hammerbrook is a quarter (Stadtteil) in the Hamburg-Mitte borough of the Free and Hanseatic city of Hamburg in Germany. In 2006, the population was 435.
Hamm, as in the Hamm section of the city that borders it to the east, refers to forest, while brook refers to the low-lying swamp or carr that formerly characterised the area, which is the confluence of the Bille with the Elbe. The name Hammer Brook originally referred to the entire area east of the city and north of the Bille extending as far as Horn.
Hamburg acquired the area from the Counts of Holstein in 1383. From the 15th century onward it was administered by a Hamburg Senator as the Landherrenschaft (Lordship) of Hamm and Horn. It was used primarily as grazing land, and drainage ditches were gradually cut. A still surviving flood basin was created in the 17th century as part of the fortifications of the city. Settlement of the area began late in that century. In 1832 the western section was incorporated in the new suburb of St. Georg, while the rest was included in the Landherrenschaft of Geestlande. In 1871 this area was divided between Borgfelde and Hamm. The current quarter of Hammerbrook was administratively created in 1938 under the Greater Hamburg Act, although a section in the east became part of the then Hamm-Süd (South Hamm).