James Conlon (born March 18, 1950) is an American conductor. He is the music director of Los Angeles Opera and principal conductor of the RAI National Symphony Orchestra.

Conlon grew up in a family of five children on Cherry Street in Douglaston, Queens, New York City. His mother, Angeline L. Conlon, was a freelance writer. His father was an assistant to the New York City Commissioner of Labor in the Robert F. Wagner administration. His siblings were not musically inclined, nor were his parents. When he was eleven, he went to a production of La traviata by the North Shore Opera. He asked for music lessons and became a treble (boy soprano) in a children's chorus in an opera company in Queens. He dreamed about being a tenor, then a baritone, and even wanted to sing the role of Carmen at one point. Finally it dawned on him that the only way to do everything in opera was to become an operatic conductor.

Conlon entered the High School of Music & Art at the age of fifteen and at eighteen he was accepted into the Aspen Music Festival and School conducting program, and in September 1968 he entered the Juilliard School of music. In 1970, the Juilliard Orchestra took an educational tour to Europe and he was invited to Spoleto the next year as an assistant doing work as a répétiteur, coach and chorus conductor. During that time, he conducted one performance of Boris Godunov. He recalled that he had fallen in love with this opera at a young age, and had dreamed that it would be the first opera he would conduct.

In 1972, at a scheduled Juilliard production of La bohème directed by Michael Cacoyannis, conductor Thomas Schippers suddenly withdrew. At the time, Maria Callas was doing a series of master classes at Juilliard and heard Conlon in rehearsal. She suggested to Juilliard's president, Peter Mennin, that Conlon should step in to conduct.

Conlon received the conducting award of the American National Orchestral Association, and in 1974 became the youngest conductor engaged for the New York Philharmonic Orchestra's subscription series. In 1976 he made his Metropolitan Opera debut and his British debut with the Scottish Opera, and in 1979 he debuted at Covent Garden. He was named director of the Cincinnati May Festival in 1979, a position he retained until 2016. After engagements with the Paris Opéra, Maggio Musicale in Florence, Rotterdam Philharmonic Orchestra and the Chicago Lyric Opera, Conlon became chief conductor of the Cologne Opera in 1989. In 1996, he was appointed music director of the Opéra National de Paris.

Since his New York Philharmonic debut in 1974 at the invitation of Pierre Boulez, Conlon has appeared with virtually every major North American and European orchestra. He has also appeared with many of the world's major opera companies, including Teatro alla Scala (Milan), the Royal Opera at Covent Garden (London), the Lyric Opera of Chicago, and the Maggio Musicale Fiorentino (Florence). Associated for almost 30 years with the Metropolitan Opera, where he made his debut in 1976, he has conducted more than 250 performances there, leading a wide range of works from the Italian, German, French, Russian and Czech repertoires.

Conlon has held several major European posts, including principal conductor of the Rotterdam Philharmonic (1983–1991), Generalmusikdirektor (GMD) of the City of Cologne, Germany (1989–2002), where he was simultaneously GMD of the Gürzenich Orchestra and the Cologne Opera, and principal conductor of the Paris National Opera (1995–2004), where his Paris tenure was the longest of any conductor there since 1939. In 2015, he was named principal conductor of the RAI National Symphony Orchestra.

Conlon has been music director of the Los Angeles Opera since the 2006–2007 season. His work there has included a series called "Recovered Voices", a multi-year project during which Conlon presented operas by composers affected by the Third Reich. The series included a double-bill of Alexander von Zemlinsky's Der Zwerg and Viktor Ullmann's Der zerbrochene Krug, and operas by composers such as Schreker and Braunfels. Conlon has conducted seven of Wagner's operas with Los Angeles Opera, including the first-ever Los Angeles performances Der Ring des Nibelungen in 2008–2009. In September 2021, the company announced the newest extension of Conlon's contract as music director, through the 2024–2025 season. In March 2024, Los Angeles Opera announced that Conlon is to conclude his tenure as its music director at the close of the 2025-2026 season, and subsequently to take the title of conductor laureate.