Born in Paris in 1971, Fayçal Karoui studied piano and conducting at the Conservatoire National Supérieur de Musique de Paris. There he obtained the first prize in orchestral conducting and subsequently joined the advanced class. He became Michel Plasson's assistant at the Orchestre National du Capitole de Toulouse, a position he held until 2002. This collaboration led him to direct a large symphonic and lyrical repertoire.

He is the Chief Conductor of the Orchestre de Pau Pays de Béarn since 2002, where he cares passionately about education and outreach, and regularly works with such top international soloists as Alexandre Kantorow, Sir Steven Hough, Alexandre Tharaud, Bertrand Chamayou, Nemanja Radulovic, Daishin Kashimoto and Gautier Capuçon. From 2012 to 2014, he succeeded Yutaka Sado as the Music Director of legendary Lamoureux Orchestra, being notably entrusted with the highly successful production of Fauré’s Pénélope in June 2013, with Roberto Alagna and Anna-Caterina Antonacci as soloists.

He guest-conducted major symphonic orchestras such as as l’Orchestre de Paris, l’Orchestre de l'Opéra National de Paris, l’Orchestre National de France, l’Orchestre Philharmonique de Radio-France, l’Orchestre National du Capitole de Toulouse, the Monte-Carlo Philharmonic, Orchestra Giuseppe Verdi in Milan, the Chamber Orchestra of Lausanne, l’Orchestre Philharmonique de Liège, the Hong-Kong Sinfonietta, the New Japan Philharmonic, and the Brussels Philharmonic.

As an internationally sought-after ballet conductor, Fayçal Karoui regularly works with top international companies, for instance the Paris Opera Ballet, Wiener Staatsballett, Royal Ballet London, Dutch National Ballet, Hong Kong Ballet, and Capitole de Toulouse. From 2006 to 2012, he served as music director of the New York City Ballet. 

In March 2013, he was named a Chevalier de l’Ordre des Arts et des Lettres by the French government.