Philippe Gilbert (born 5 July 1982) is a Belgian professional road bicycle racer for UCI ProTour team Quick-Step Floors. Gilbert is best known for winning the World Road Race Championships in 2012, and for being one of two riders, along with Davide Rebellin, to have won the three Ardennes classics – the Amstel Gold Race, La Flèche Wallonne and Liège–Bastogne–Liège – in a single season, which he accomplished in 2011. Gilbert also finished the 2011 season as the overall winner of the UCI World Tour. Gilbert was accused of abusing Cortisone by an anonymous former Lotto teammate during this dominant period with Omega Pharma–Lotto, an allegation which the Belgian vehemently denies.

A Classics specialist, Gilbert has won several classic cycle races, including Paris–Tours twice (2008, 2009), the Giro di Lombardia twice (2009, 2010), the Amstel Gold Race three times (2010, 2011, 2014), La Flèche Wallonne (2011), Liège–Bastogne–Liège (2011) and the Clásica de San Sebastián (2011). He has also won stages at each of the three cycling Grand Tours; he won three stages at the Giro d'Italia, winning one in 2009 and two in 2015, a stage at the Tour de France in 2011, and five stages at the Vuelta a España, winning two in both 2010 and 2012, and one in 2013. He is the second person (and first Belgian) in history to win all three Ardennes classics in a single year.