| Honorific-Prefix: | The Honorable |
| Romanzo Bunn | |
| Office: | United States district judge for the |
| Term Start: | October 30, 1877 |
| Term End: | January 9, 1905 |
| Appointer: | Rutherford B. Hayes |
| Predecessor: | James C. Hopkins |
| Successor: | Arthur Loomis Sanborn |
| Office1: | Wisconsin Circuit Court Judge |
| Appointer1: | Lucius Fairchild |
| Term Start1: | 1868 |
| Term End1: | 1877 |
| Predecessor1: | Edwin Flint |
| Successor1: | Alfred W. Newman |
| State2: | Wisconsin |
| State Assembly2: | Wisconsin |
| District2: | Buffalo - Jackson - Trempealeau |
| Term Start2: | January 1, 1860 |
| Term End2: | January 1, 1861 |
| Predecessor2: | Jesse Bennett |
| Successor2: | Calvin R. Johnson |
| Birth Name: | Romanzo Norton Bunn |
| Birth Date: | 24 September 1829 |
| Birth Place: | South Hartwick, New York |
| Death Place: | Madison, Wisconsin |
| Restingplace: | Forest Hill Cemetery Madison, Wisconsin |
| Party: | Republican |
| Spouse: | Sarah Purdy Bunn |
| Education: | read law |
| Signature: | Romanzo Bunn sig.png |
Romanzo Norton Bunn (September 24, 1829 - January 25, 1909) was an American lawyer and judge. He was a United States district judge of the Western District of Wisconsin, a Wisconsin Circuit Court Judge, and a member of the Wisconsin State Assembly.
Born in South Hartwick, New York, Bunn read law to enter the bar in 1853. He was in private practice in Ellicottville, New York, from 1853 to 1854, and then in Galesville, Wisconsin, until 1861. He was district attorney in Galesville from 1857 to 1858. He was a Republican member of the Wisconsin State Assembly in 1859, returning to private practice in Sparta, Wisconsin, from 1861 to 1868. He was a Judge of the Wisconsin Circuit Court for the 6th Judicial Circuit from 1868 to 1877. He was a Professor of law at the University of Wisconsin from 1878 to 1885.[1]
On October 25, 1877, Bunn was nominated by President Rutherford B. Hayes to a seat on the United States District Court for the Western District of Wisconsin vacated by Judge James C. Hopkins. Bunn was confirmed by the United States Senate on October 30, 1877, and received his commission the same day. Bunn served in that capacity until his retirement on January 9, 1905.
Bunn died on January 25, 1909, in Madison, Wisconsin. His former home there is located in what is now the Langdon Street Historic District.[2]