The 85th running of Liège-Bastogne-Liège was held on 18 April 1999. It was the fourth leg of the 1999 UCI Road World Cup, held between Paris-Roubaix and Amstel Gold Race. Belgian Frank Vandenbroucke won the race after a solo attack on the Côte de Saint-Nicolas. Dutchmen Michael Boogerd and Maarten den Bakker completed the podium. 71 of 191 riders finished the race.