Robert Otto Homburg (31 January 1876 – 21 October 1948) was an Australian politician who represented the South Australian House of Assembly multi-member seat of Burra Burra from 1912 to 1915 representing the Liberal Union. He resigned in 1915 to devote more time to the legal practice that both he and Hermann Homburg were partners in. He had also been the subject of "gross slanders" about his loyalty, due to their father having immigrated from Germany. Homburg was an alderman in the Adelaide City Council for many years.