Otto Julius Klotz OLS, DLS, DTS (March 31, 1852 – December 28, 1923) was a Canadian astronomer and Dominion Surveyor. He was born in Preston (Cambridge), Upper Canada, the son of Otto Klotz and Elise (Elizabeth) Wilhelm, Klotz was educated at Galt Grammar School, and later headed to University of Toronto, and finished his degree in 1872 in Civil Engineering at the University of Michigan in Ann Arbor, Michigan. He died in Ottawa on December 28, 1923.