The De Geer family (Dutch: [də ˈɣeːr], Swedish: [dœˈjæːr]; also: De Geer van Jutphaas and De Geer van Oudegein) is a prominent industrial family of Walloon origin that belongs to the Swedish and Dutch nobility.

The name derives from the town of Geer near Liège (in present-day Belgium).

[1][2] His descendant Louys de Geer (1535–1602) moved from Liège to Aachen and later to Dordrecht in the Dutch Republic for religious reasons.

Subsequent generations became notable in Sweden and the Netherlands from the early 17th century, mainly centered on the iron-foundry company town Finspång, but often extending to science, art and national politics.

The larger, Swedish branch of the family retained its contacts with the Netherlands.