| William Hitz | |
| Office: | Associate Justice of the United States Court of Appeals for the District of Columbia |
| Term Start: | February 6, 1931 |
| Term End: | July 3, 1935 |
| Appointer: | Herbert Hoover |
| Predecessor: | Seat established by 46 Stat. 785 |
| Successor: | Harold Montelle Stephens |
| Office1: | Associate Justice of the Supreme Court of the District of Columbia |
| Term Start1: | November 15, 1916 |
| Term End1: | February 13, 1931 |
| Appointer1: | Woodrow Wilson |
| Predecessor1: | Thomas H. Anderson |
| Birth Name: | William Hitz |
| Birth Date: | 21 April 1872 |
| Birth Place: | Washington, D.C. |
| Education: | Harvard University Georgetown Law (LLB) |
William Hitz (April 21, 1872 – July 3, 1935) was an Associate Justice of the United States Court of Appeals for the District of Columbia and previously was an associate justice of the Supreme Court of the District of Columbia.
Born in Washington, D.C., Hitz received his undergraduate education from Harvard University, and received a Bachelor of Laws from Georgetown Law in 1900. He was in private practice in Washington, D.C. from 1900 to 1914 and was a special attorney at the United States Department of Justice from 1914 to 1916.
Hitz received a recess appointment from President Woodrow Wilson on November 15, 1916, to an Associate Justice seat on the Supreme Court of the District of Columbia (now the United States District Court for the District of Columbia) vacated by Associate Justice Thomas H. Anderson. He was nominated to the same position by President Wilson on December 15, 1916. He was confirmed by the United States Senate on January 2, 1917, and received his commission the same day. His service terminated on February 13, 1931, due to his elevation to the District of Columbia Circuit.
Hitz was nominated by President Herbert Hoover on January 5, 1931, to the Court of Appeals for the District of Columbia (United States Court of Appeals for the District of Columbia from June 7, 1934, now the United States Court of Appeals for the District of Columbia Circuit), to a new Associate Justice seat authorized by 46 Stat. 785. He was confirmed by the United States Senate on January 28, 1931, and received his commission on February 6, 1931. His service terminated on July 3, 1935, due to his death.