The city's previous longest serving mayor, the late Kevin White, was in office for four terms, from 1968 to 1984.
Menino's longevity also exceeded the legendary Mayor James Michael Curley, who also served four terms, but not consecutively.
Menino built his reputation by focusing on the unglamorous nuts and bolts of running a major metropolitan city — fixing potholes, cleaning streets, even curbing the practice of saving a shoveled-out parking space by putting folding chairs or trash cans along the curb.
It's everyday commitments like those that earned him the nickname of the "Urban Mechanic."
The 2004 Democratic National Convention put Menino's political and negotiating skills to the test when the city's main police union threatened to picket over an unresolved contract.
It was only with the last minute help of other politicians, including Republican Gov. Mitt Romney, that a contract was reached in the early morning hours the day before the convention opened.
During his years in office, Menino also became a vigorous national voice in favor of stricter gun control measures.
He co-founded Mayors Against Illegal Guns with New York Mayor Michael Bloomberg and criticized the National Rifle Association's call for more armed guards at schools after the Connecticut school shooting in December.
"That is crazy," Menino said. "Every victim of gun violence and their families knows that's crazy."
Menino also built a reputation for creating an impressive political machine that handily defeated challengers.
Last year, Menino also played a crucial role in helping elect U.S. Sen. Elizabeth Warren, campaigning with her at stops across the city.
Associated Press writer Bob Salsberg contributed to this report.