The Little Mermaid is a 1989 American animated musical fantasy film produced by Walt Disney Feature Animation and released by Walt Disney Pictures. It is loosely based on the 1837 Danish fairy tale of the same name by Hans Christian Andersen. The film was written and directed by John Musker and Ron Clements and produced by Musker and Howard Ashman, who also wrote the film's songs with Alan Menken. Menken also composed the film's score. Featuring the voices of René Auberjonois, Christopher Daniel Barnes, Jodi Benson, Pat Carroll, Paddi Edwards, Buddy Hackett, Jason Marin, Kenneth Mars, Ben Wright and Samuel E. Wright, The Little Mermaid tells the story of a teenage mermaid princess named Ariel, who dreams of becoming human and falls in love with a human prince named Eric, which leads her to make a magic deal with the sea witch, Ursula, to become human and be with him.

Walt Disney planned to put the story in a proposed package film containing Andersen's stories, but scrapped the project. In 1985, while working on The Great Mouse Detective (1986), Clements and Musker decided to adapt the fairy tale and proposed it to Walt Disney Studios chairman Jeffrey Katzenberg, who initially declined due to its similarities to a proposed sequel to the 1984 film Splash, but ultimately approved of it. Ashman became involved and brought in Menken. With supervision from Katzenberg, they made a Broadway-style structure with musical numbers as the staff was working on Oliver & Company (1988). Katzenberg warned that the film would earn less since it appealed to female viewers, but he eventually became convinced that it would be Disney's first blockbuster hit.

The Little Mermaid was released to theaters on November 17, 1989, to critical acclaim, earning praise for the animation, music, and characters. It was also a commercial success, garnering $84 million at the domestic box office during its initial release, and $235 million in total lifetime gross worldwide, becoming the sixth-highest-grossing film of 1989. Along with the major success of both Disney's 1986 animated film The Great Mouse Detective and the 1988 Disney/Amblin live-action/animated film Who Framed Roger Rabbit, The Little Mermaid is given credit for breathing life back into the art of Disney animated feature films after some films produced by Disney were struggling. It also marked the start of the era known as the Disney Renaissance. The film won two Academy Awards for Best Original Score and Best Original Song ("Under the Sea").

The film's success led to a media franchise. A direct-to-video sequel was released in 2000, focusing on Ariel's daughter, Melody. A prequel followed in 2008. The first film was adapted into a stage musical with a book by Doug Wright and additional songs by Alan Menken and new lyricist Glenn Slater opened in Denver in July 2007 and began performances on Broadway January 10, 2008 starring Sierra Boggess.Other derived works and material inspired by the film, include a 2019 live musical presentation on ABC as part of The Wonderful World of Disney, and a 2023 live-action film adaptation directed by Rob Marshall and starring Halle Bailey.

In 2022, the film was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant".