Johannes Marijnus Antonius Maria "Jan" de Wit (born 10 May 1945) is a former Dutch politician and lawyer.

de Wit studied public law at Tilburg University.

For a brief time, he worked as a lawyer in Eindhoven and thereafter for many years in Maastricht and Heerlen.

In 1995, de Wit was elected into the Dutch Senate; he was the sole representative of the SP until 1998.

From 24 June 2009 to October 2010 de Wit was the chairman of the Temporary Committee on Financial System Inquiry [nl], which was to investigate the causes of the credit crisis.