Alain Lamassoure graduated at the Paris Institute of Political Studies and at the École Nationale d'Administration (ENA). He started his career in 1968 as an auditor at the Court of Auditors, then he worked as a special adviser for the Minister for Cultural Affairs, technical adviser in the office of the Minister for Finance, of the Minister for Infrastructure and of the President of the Republic of France. Later he worked as a senior advisor at the Court of Auditors.
Since 1989 he is a member of the European Parliament. He was a member of the Liberal and Democratic Reformist Group, member of the Group of the European People's Party (Christian-Democratic Group), member of the Group of the European People's Party (Christian Democrats) and European Democrats. He is actually a member of the Christian Democrats. Lamassoure was Chair of the Committee on Budgetary Control, Chair of the Committee on Budgets, Chair of the Special Committee on Tax Rulings and Other Measures Similar in Nature or Effect, Vice-Chair of the Committee on Budgets, Vice-Chair of the Delegation for relations with the Maghreb countries and the Arab Maghreb Union, Vice-Chair of the Delegation for relations with South Africa. He was member of the Committee on Budgets, member of the Committee on Budgetary Control, member of the Delegation for relations with the Maghreb countries and the Arab Maghreb Union, member of the Committee on Energy, Research and Technology, member of the Committee on Industry, External Trade, Research and Energy, member of the Committee on Foreign Affairs, Human Rights, Common Security and Defense Policy, member of the Delegation to the EU-Cyprus Joint Parliamentary Committee, member of the Delegation for relations with the countries of south-east Europe, member of the Delegation for relations with the countries of South Asia and the South Asia Association for Regional Cooperation (SAARC), member of the Temporary committee on policy challenges and budgetary means of the enlarged Union 2007-2013, member of the Delegation for relations with India, member of the Conference of Committee Chairs, member of the Special committee on the policy challenges and budgetary resources for a sustainable European Union after 2013, member of the Committee on Economic and Monetary Affairs, member of the Delegation for relations with the countries of South Asia, member of the Special Committee on Tax Rulings and Other Measures Similar in Nature or Effect, member of the Committee of Inquiry to investigate alleged contraventions and maladministration in the application of Union law in relation to money laundering, tax avoidance and tax evasion. Since 2017 he is a member of the Committee on Constitutional Affairs.