Karl Lenz (7 July 1899 in Heidelberg – 7 November 1944 in Freising) was a Nazi Party (NSDAP) official who served as the third and last Gauleiter of Gau Hesse-Darmstadt.

After attending primary and high school, he volunteered for service in World War I in November 1916 with Mecklenburg Jäger Battalion 14.

[1] On 16 September 1931 following the death of Peter Gemeinder, Lenz was appointed Gauleiter of Gau Hesse-Darmstadt, which consisted of the People's State of Hesse.

In November 1932, Sprenger wrote a report to the Party Reichsleitung (National Leadership) demanding the ouster of Lenz as Gauleiter, alleging that he spent less time running his Gau than cultivating various sexual relationships.

On 1 April 1934 he was found guilty of conduct damaging to the Party, given a formal reprimand and banned from holding political office for three years.

[4] In September 1941, he was allowed to join the Allgemeine SS, given the rank of SS-Sturmbannführer and assigned to the Reich Security Main Office.

On 26 February 1943 he joined the Waffen-SS but remained in an administrative position in the SS Main Office in Berlin under Gottlob Berger.

In March 1943, his final assignment was as the business manager for DeVlag, the Nazi organization in Flanders that was active in recruiting members for the Waffen-SS.