Otto Lenz (6 July 1903, Wetzlar, Rhine Province - 2 May 1957, Naples) was a German politician (CDU), serving from 1951 – 1953 as Head of the Chancellery and from 1953 until his death as a member of the German Bundestag. He was also a signatory of the founding declaration of the CDU.
After completing his Abitur, Lenz began studying law at the University of Freiburg. He completed his studies at the University of Marburg in 1924, receiving his doctorate in 1925 with a dissertation entitled Die Haftung bei Gattungsschulden in § 279 BGB (The Liability of Generic Debt in § 279 BGB). After passing the Staatsexamen, Lenz joined the Administration of Justice and quickly began working in Germany's Federal Ministry of Justice. He became director of the Ministry's press office in 1929 and served in this office for four years, during which he experienced considerable success in developing a strong relationship with the German press. In 1932 he began working as the personal advisor of state secretary Heinrich Hölscher.
After the Machtergreifung in January 1933, Lenz's title was changed to Advisor of Commercial Law in the Reichsjustizamt. One year later, in April 1934, he was promoted to the position of Landgerichtsdirektor despite the protest of the National Socialist lawyer's association. His first act of defiance to the Nazi-Regime occurred in 1938, when he refused a job transfer due to his unwillingness to work as a judge in the Nazi legal system. He worked instead as a lawyer during this time, being admitted only with serious difficulty to the Kammergericht.