Ranald Norman Munro MacLean, Lord MacLean (born 18 December 1938) is a retired Scottish judge.

Born on 18 December 1938, MacLean was educated at Fettes College in Edinburgh, where he was Head of School. He graduated BA from Clare College, Cambridge, LLB from the University of Edinburgh and LLM from Yale University.

Admitted to the Faculty of Advocates in 1964, MacLean served as an Advocate Depute from 1972–1975 and was the Home Advocate Depute from 1979–1982. He was appointed Queen's Counsel (QC) in 1977.

MacLean was appointed a Senator of the College of Justice in 1990, serving until 2005. He has been a member of various bodies, including the Scottish Legal Aid Board, the Council on Tribunals, the Parole Board for Scotland, the Secretary of State's Criminal Justice Forum and the Stewart Committee on Alternatives to Prosecution. He was Chairman of a committee established by the Secretary of State for Scotland to review the sentencing and treatment of serious sexual and violent offenders including those with personality disorders in 1999. He also chaired the inquiry into the death of loyalist leader Billy Wright in the Maze Prison (see The Billy Wright Inquiry).

MacLean is a former member of the Judicial Appointments Board for Scotland, and, with two other judges and five lay members, is responsible for selecting all new Scottish judges and sheriffs.

He has been chairman of the governors of Fettes College since 1996, and was chairman of the council of the Cockburn Association from 1988–1996.