Theodore Oesten (also Theodor in German) (December 31, 1813, Berlin ? March 16, 1870, Berlin) was a German composer, musician, and music teacher.
Oesten learned to play wind and string instruments from the Stadtmusikus in Fürstenwalde (a small town outside Berlin). At the age of nineteen he studied composition with Böhmer, Rungenhagen, Schneider, and A. W. Bach in Berlin. Oesten is perhaps best known for his easy to play piano compositions, including transcriptions of operatic works, written in the sentimental style of his day. His son Max also became a composer.