Brian Peter MacDonell, QSO (born 19 May 1935), is a former New Zealand Member of Parliament for Dunedin Central in the South Island.
He was born in Dunedin on 19 May 1935, the son of Roderick MacDonell. He received his education at Christian Brothers High School, since renamed Kavanagh College. He became active with the labour movement in 1950. In 1958, he married Joan Banwell, the daughter of William Banwell. The MacDonells have four sons.
MacDonell worked for a bank from 1953 to 1963, and was a national councillor for the New Zealand bank officers union. He represented the Dunedin Central electorate in Parliament for 21 years from 1963 to 1984. He was Parliamentary Under-Secretary to the Minister of Trade and Industry (1973–1975) and to the Minister of Energy Resources (1974–1975). Following the Royal Commission on Contraception, Sterilisation and Abortion, parliament discussed legislation to legalise abortion, and MacDonell supported his pro-life stance by holding a jar with a pickled 12-week-old foetus during the debate. Parliament passed the Contraception, Sterilisation, and Abortion Act 1977.
The Dunedin Central electorate was abolished in the 1983 electoral redistribution, and the electorate of Dunedin West was established in its place. MacDonell was not selected as the Labour candidate for the new electorate of Dunedin West; instead, the party's president, Jim Anderton, installed his personal friend Clive Matthewson. MacDonell stood as an Independent in the 1984 general election but was not successful.
In the 1993 New Year Honours, MacDonell was made a Companion of the Queen's Service Order for public services. MacDonell now resides in Tasmania, Australia. MacDonell enjoys fishing for recreation.