Gerardus Johannes Delfgaauw, (Monster, April 2, 1882 - Rijswijk, October 21, 1947) was a Dutch painter.

After training at the drawing academy in The Hague around the turn of the century, Gerard Delfgaauw worked in a naturalistic-impressionist style. He painted many landscapes and cityscapes (including Amsterdam, Rotterdam, Dordrecht and Delft). His work includes a series of dynamic Rotterdam harbor views, including De Nieuw Amsterdam and the Statendam moored at the Wilhelminakade.

There are paintings by Delfgaauw, which were signed by an art dealer with H. van Gessel; this only lasted for a short period of time. Paintings bearing the signature K. Schilderspel or J. van Delden have nothing to do with the work of G.J. Delfgaauw. These names have been used for commercial reasons for the sale of works not made by Delfgaauw. Art historical research has shown that these paintings are completely different in both style and technique; they are not difficult for experts to distinguish from a real Delfgaauw. The results of the investigation could be confirmed by the painter's son.