| Honorific Prefix: | The Honorable |
| Donald W. Steinmetz | |
| Office: | Justice of the Wisconsin Supreme Court |
| Term Start: | August 1, 1980 |
| Term End: | September 1999 |
| Predecessor: | Connor Hansen |
| Successor: | Diane S. Sykes |
| Term Start1: | August 1, 1978 |
| Term End1: | August 1, 1980 |
| Predecessor1: | Transitioned from County Court |
| Successor1: | Thomas P. Doherty |
| Office2: | County Judge for |
| Term Start2: | January 1, 1966 |
| Term End2: | July 31, 1978 |
| Predecessor2: | Herbert A. Schultz |
| Successor2: | Transitioned to Circuit Court |
| Birth Date: | 19 September 1924 |
| Birth Place: | Milwaukee, Wisconsin |
| Death Place: | Milwaukee, Wisconsin |
| Restingplace: | Holy Cross Cemetery Milwaukee, Wisconsin |
| Profession: | lawyer, judge |
| Father: | Christian Steinmetz |
| Mother: | Bessie (Engel) Steinmetz |
| Allegiance: |  United States |
| Serviceyears: | 1943–1945 |
| Battles: | World War II |
Donald Walter Steinmetz (September 19, 1924August 31, 2013) was an American lawyer and judge. He served as a justice of the Wisconsin Supreme Court for 19 years, and before that was a trial judge in Milwaukee County for 14 years.
Born in Milwaukee, Wisconsin, Steinmetz served in the United States Army Air Forces during World War II. Steinmetz then graduated from the University of Wisconsin - Madison and received his law degree from the University of Wisconsin Law School. Steinmetz was a claims attorney before his service in government. Between 1958 and 1966, he worked as an assistant Milwaukee city attorney, an assistant district attorney in Milwaukee County, and an assistant Wisconsin Attorney General. In 1964, he was the preferred candidate of Democratic leaders, including Governor John W. Reynolds, Jr., to replace deceased Milwaukee County District Attorney William McCauley, but the post went to Hugh O'Connell. He was a Wisconsin county judge and later a Wisconsin Circuit Court judge for Milwaukee County after the county courts were combined into the circuit courts. He was also a teacher at the Wisconsin Judicial College. He was elected to the Wisconsin Supreme Court in 1980 and re-elected in 1990.[1] [2]
He died on August 31, 2013, in Milwaukee.[3]