Otto Dimroth (28 March 1872 – 16 May 1940) was a German chemist. He is known for the Dimroth rearrangement, as well as a type of condenser with an internal double spiral, the Dimroth condenser. He made pioneering contributions to organomercury chemistry.

His son Karl Dimroth was also a renowned chemist, who described the first synthesis of 3-benzoxepin.

  • L. Ebert (1941). "Obituary: Otto Dimroth. 1872-1940". Berichte der Deutschen Chemischen Gesellschaft. 74 (1): A1–A23. doi:.