Rear Admiral John Marshall Bowyer (19 June 1853 – 15 March 1912) was an officer in the United States Navy. Bowyer was born in Cass County, Indiana; and in 1870, he was appointed to the United States Naval Academy from Iowa. He graduated from the Naval Academy in 1874. Ensign Bowyer served aboard the ship Michigan attached to the Northwestern Lake station. From 1881 through 1884, he was on the sloop Wachusett in the Pacific. For the next three years, Bowyer was attached to the North Atlantic Station, serving on the cruisers Detroit and Raleigh, and the ill-fated battleship Maine.