| James J. Bruin | |
| State House: | Massachusetts |
| District: | 15th Middlesex |
| Predecessor: | Seat created |
| Successor: | James O'Dea Jr. |
| Term Start: | January 5, 1949 |
| Term End: | January 26, 1949 |
| Office1: | Member of the Lowell City Council |
| Term Start1: | 1948 |
| Term End1: | 1950 |
| Office2: | Mayor of Lowell, Massachusetts |
| Term Start2: | 1934 |
| Term End2: | 1935 |
| Predecessor2: | Charles H. Slowey |
| Successor2: | Dewey G. Archambault |
| Office3: | Member of the Lowell School Committee |
| Term Start3: | 1923 |
| Term End3: | 1925 |
| Birth Date: | 31 October 1898 |
| Birth Place: | Lowell, Massachusetts, U.S. |
| Death Place: | Lowell, Massachusetts, U.S. |
| Resting Place: | St. Patrick's Cemetery |
| Party: | Democratic |
| Education: | Northeastern Law School (LL.B) |
| Occupation: | Lawyer |
| Allegiance: | United States |
| Branch: | Judge Advocate General's Corps |
| Rank: | Captain |
James J. Bruin (October 31, 1898 – January 26, 1949) was an American politician from Lowell, Massachusetts.
Bruin was born on October 31, 1898, in Lowell. In 1922 he graduated from the Northeastern University School of Law.[1]
Bruin served on the Lowell school committee from 1923 to 1925. In 1932 he was the Democratic nominee for the United States House of Representatives seat in Massachusetts's 5th congressional district, but lost to incumbent Edith Nourse Rogers. From 1934 to 1935 he was the mayor of Lowell. In 1934 he was the Democratic nominee for Middlesex County District Attorney, but lost to incumbent Warren L. Bishop.[2] In 1948, Bruin returned to elected office as a member of the Lowell city council. Later that year he was elected to the Massachusetts House of Representatives. However, Bruin died on January 26, 1949, soon after taking office.