In 2006 according to the statistical office of Hamburg and Schleswig-Holstein, the quarter Alsterdorf has a total area of . The river Alster floating from Northeast to Southwest is the border to the Groß Borstel quarter in the West. In the South Alsterdorf borders to Winterhude quarter. In the East is the Quarter Ohlsdorf.
Parts of the large Ohlsdorf Cemetery (Ohlsdorfer Friedhof ) belongs to the quarter Alsterdorf.
In 1999 there were 6,508 households out of which 15.3% had children under the age of 18 living with them and 54.4% of all households were made up of individuals. The average household size was 1.77.
Population by year
| 1987 | 1988 | 1989 | 1990 | 1991 | 1992 | 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 |
| 12,455 | 12,487 | 12,551 | 12,563 | 12,520 | 12,449 | 12,622 | 12,577 | 12,476 | 12,209 | 12,027 | 11,847 | 11,827 |
| 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 |
| 12,180 | 12,379 | 12,480 | 12,723 | 12,825 | 12,872 | 12,955 |
In 2006 there were 1,283 criminal offences (99 crimes per 1,000 people).
There were 1 elementary school and 2 secondary schools in the quarter Alsterdorf and 30 physicians in private practice and 5 pharmacies.
Alsterdorf is serviced by the rapid transit system of the underground railway . According to the Department of Motor Vehicles (Kraftfahrt-Bundesamt), in the quarter were 4,847 private cars registered (377 cars/1000 people).