Laurens Jan Brinkhorst studied law at the University of Leiden, where he obtained his LL.M. degree in 1959. He received also an M.A. degree in Public Law and Government from Columbia University in New York City. Afterwards he worked at Shearman & Sterling in New York City. From 1962, and from 1965 as a director, he worked at the Europe-institute at the Rijksuniversiteit Leiden where he became a Lector in 1965. During the period 1967-1973 he was Professor of European Law at the University of Groningen. He began his political career in 1973, when he became Deputy Minister of Foreign Affairs.
Between July 1994 and June 1999 he was member of the European Parliament. During this period Brinkhorst was member of the Group of the European Liberal, Democrat and Reform Party, Vice-Chair of the Delegation for relations with the People's Republic of China, member of the Committee on Budgets, member of the Delegation for relations with the United States and member of the Delegation for relations with the People's Republic of China.