Cornelis "Kees" van Geelkerken was a Dutch political leader and civil servant.
Van Geelkerken was born in 1901 to a Dutch family in Molenbeek-Saint-Jean, Belgium, and grew up in Utrecht. He gravitated toward fascism in the 1920s while working as a municipal employee in Zeist and Utrecht. Van Geelkerken co-founded the far-right National Socialist Movement in the Netherlands with Anton Mussert in 1931. He was made the leader of the Nationale Jeugdstorm, the party's youth corps.
In 1943, during the German occupation of the Netherlands, Van Geelkerken was appointed Inspector-General of the Nederlandse Landwacht, a collaborationist paramilitary created by the Germans to combat the Dutch resistance. He was expelled from the NSB in early 1945 after a falling out with Mussert. After the war, he was tried in the Bijzonder Gerechtshof and sentenced to life imprisonment, but was later released in 1959. He died in 1976 in Ede.