Céline Marie Claudette Dion ( say-LEEN dee-ON, French: [selin maʁi klodɛt djɔ̃]; born 30 March 1968) is a Canadian singer. Referred to as the "Queen of Power Ballads", she is noted for her powerful and technically skilled vocals. Her music has incorporated genres such as pop, rock, R&B, chanson, and classical music. Her recordings have been mainly in English and French, although she has also sung in several other languages including Japanese, Italian, German, Mandarin, Spanish and Neapolitan.

Born into a large family in Charlemagne, Quebec, Dion was discovered by her future manager and husband, René Angélil, and emerged as a teen star in her home country with a series of French-language albums during the 1980s. She gained international recognition by winning the 1988 Eurovision Song Contest, where she represented Switzerland with "Ne partez pas sans moi". Her debut English-language album, Unison (1990), established her as a viable pop artist primarily in North America and several English-speaking markets, while The Colour of My Love (1993) gave her global superstardom. Dion continued her success throughout the 1990s with several of the bestselling albums in history, such as Falling into You (1996) and Let's Talk About Love (1997), which were certified diamond in the U.S. with more than 30 million sales worldwide each. She also released a series of international number-one hits, including "The Power of Love", "Think Twice", "To Love You More", "Because You Loved Me", "It's All Coming Back to Me Now", "I'm Your Angel", "That's the Way It Is", "I'm Alive" and "My Heart Will Go On", the theme for the 1997 film Titanic, which solidified her popularity.

Dion continued releasing French-language albums between each English record; D'eux (1995) became the best-selling French-language album of all time, while S'il suffisait d'aimer (1998), Sans attendre (2012), and Encore un soir (2016), were all certified diamond in France. During the 2000s, she built her reputation as a successful live performer with A New Day... on the Las Vegas Strip (2003–07), the highest-grossing concert residency of all time, and the Taking Chances World Tour (2008–09), one of the highest-grossing concert tours of the 2000s. In 2009, she was named by the Los Angeles Times as the top-earning artist of the decade, with combined album sales and concert revenue exceeding $747 million. In 2022, Dion canceled a tour due to her diagnosis of stiff-person syndrome, a rare neurological disease.

With over 200 million records sold worldwide, Dion is the best-selling Canadian recording artist, the best-selling French-language artist, and one of the best-selling musical artists of all time. She is the sixth most successful female artist in the history of U.S. Billboard 200 and received recognition from the IFPI for selling over 50 million albums in Europe. Seven of her albums have sold at least 10 million copies worldwide, the second most among women in history. She was ranked as the fourth most outstanding pop vocalist by Cover Magazine and the ninth greatest voice in music by MTV. One of the highest-grossing touring artists in history, she is the second woman to accumulate US$1 billion in concert revenue. According to Forbes, Dion was the world's highest-paid female musician in 1997, 1998, 2004, and 2006. She received honorary doctorates in music from Berklee College of Music and Université Laval.