Pieter Jacobus "Koos" Verdam (15 January 1915 – 11 March 1998) was a Dutch politician of the defunct Anti-Revolutionary Party (ARP) now merged into the Christian Democratic Appeal (CDA). The reformed Verdam was a professor for Roman law and international civil law at the Vrije Universiteit Amsterdam and from 1959 to 1960 its Rector Magnificus. From 1966 to 1967 he was the Minister of the Interior and Kingdom Relations in the Cabinet Zijlstra. In 1970 he became the Queen's Commissioner in Utrecht.