Johann Adam Otto Bütschli (3 May 1848 – 2 February 1920) was a German zoologist and professor at the University of Heidelberg.

He moved to Heidelberg in 1866 and worked with Robert Bunsen (chemistry).

He received his PhD from the University of Heidelberg in 1868, after passing examinations in geology, paleontology, and zoology.

After leaving his studies to serve as an officer in the Franco-Prussian War (1870–1871), Bütschli worked in his private laboratory and then for two years (1873–1874) with Karl Möbius at the University of Kiel.

He became professor at the University of Heidelberg, as successor of Alexander Pagenstecher, in 1878.