| Dieter Haaßengier | |
| Birth Date: | 1934 5, df=y |
| Birth Place: | Dimmen, Gau Pomerania, Germany |
| Death Place: | Garbsen, Lower Saxony, Germany |
| Nationality: | German |
| Party: | CDU |
| Office: | Member of the Landtag of Lower Saxony |
| Term Start: | 21 June 1970 |
| Term End: | 25 February 1976 |
Dieter Haaßengier (30 May 1934 – 7 February 2023) was a German politician. A member of the Christian Democratic Union, he served in the Landtag of Lower Saxony from 1970 to 1976.
Haaßengier died in Garbsen on 7 February 2023, at the age of 88.[1]