John W. Costello is an American attorney and politician who served as a member of the Massachusetts House of Representatives, the Massachusetts Governor's Council, and was the Democratic nominee for Lieutenant Governor of Massachusetts in 1964.
Costello was born on April 30, 1927 in Boston.  He graduated from Cathedral High School and went on to attend the College of the Holy Cross, where he majored in political science, played end for the Holy Cross Crusaders football team, and was a member of the school's swim team.
In 1950, while a senior at Holy Cross, Costello ran for one of the 18th Suffolk district seats in the Massachusetts House of Representatives.
In 1961, he was selected by the Massachusetts General Court to fill a vacancy on the Massachusetts Governor's Council caused by Edward J. Cronin's appointment as clerk of the Newton District Court. He was chosen over fellow representative Anthony Colonna 25 votes to 5 in the Senate and 125 to 99 in the House. Costello was elected to the Council in his own right in 1962 and reelected in 1964.
On May 18, 1964, Costello announced his candidacy for Lieutenant Governor.
In 1966, Costello was again a candidate for Lieutenant Governor.
In 1998, Costello ran for his old seat on the Governor's Council.