Joan Colom i Naval was born on 5 July 1945 in Barcelona, Spain. He received his doctorate in Economic and Business Sciences from the Autonomous University of Barcelona in 1976 and he is a full professor of Applied Economics at the Faculty of Economics of the University of Barcelona, specializing in tax federalism. In 1982 he began his political career. From January 1986 to February 2004 he was member of the European Parliament. During this period he was member of the Socialist Group, member of the Group of the Party of European Socialists, Vice-Chair of the Parliament's Bureau, Vice-Chair of the Parliament's Bureau, member of the Committee on Budgets, member of the Committee on Budgetary Control, member of the Delegation for relations with the People's Republic of China, member of the Committee on Economic and Monetary Affairs and Industrial Policy, member of the Members from the European Parliament to the Joint Assembly of the Agreement between the African, Caribbean and Pacific States and the European Union (ACP-EU).
In 2004, he was appointed Deputy Mayor of the Audit Office of the Accounts of Catalonia, a post in which he was renewed in 2007 until 2010. In 2011 he rejoined his position as Professor Titular of the University of Barcelona.