| Peter Mills | |
| Office1: | United States Attorney for the District of Maine |
| President1: | Richard Nixon Gerald Ford |
| Term Start1: | September 1969 |
| Term End1: | January 20, 1977 |
| Predecessor1: | Lloyd P. LaFountain |
| Successor1: | George J. Mitchell |
| President2: | Dwight D. Eisenhower |
| Term Start2: | August 17, 1953 |
| Term End2: | January 20, 1961 |
| Predecessor2: | Alton A. Lessard |
| Successor2: | Alton A. Lessard |
| State Senate3: | Maine |
| District3: | 21st |
| Term Start3: | January 4, 1967 |
| Term End3: | September 1969 |
| Preceded3: | Sidney D. Maxwell |
| Succeeded3: | Joseph F. Holman |
| Birth Name: | Sumner Peter Mills Jr. |
| Birth Date: | 26 August 1911 |
| Birth Place: | Farmington, Maine, U.S. |
| Death Place: | Farmington, Maine, U.S. |
| Party: | Republican |
| Children: | 5, including Peter and Janet |
| Education: | Colby College (AB) Boston University (LLB) |
| Allegiance: |  United States |
| Branch: | United States Navy |
| Rank: | Captain |
| Battles: | World War II |
Sumner Peter Mills Jr. (August 26, 1911 – September 22, 2001) was an American attorney and politician from Maine.[1] He is the father of Governor Janet Mills and State Senator Sumner Peter Mills III.
Mills was born on August 26, 1911, in Farmington, Maine, to Sumner Peter Mills and the former Flora Pearson. He attended Hebron Academy, Colby College, and Boston University School of Law.