Theodore Bendix or Theo. Bendix (July 25, 1862 – January 15, 1935) was an American composer, classical violinist, musical director, and opera conductor. He became a professional musician at the age of thirteen and was hired as a conductor for an opera company when he was sixteen. Before he was eighteen, he had written the music for the show, resulting in the hit song "My Sweetheart".

Bendix worked with numerous theaters and opera companies and was a musical director and composer with Florenz Ziegfeld, Henry Wilson Savage, Klaw and Erlanger. He was the musical director for several Broadway shows, including The Belle of New York, Ben-Hur, and Beauty and the Beast. He also established a music publishing firm, Theo Bendix Music Publishing Co. in New York City. In his time, Bendix was one of the best-known musical directors of popular music.