SpongeBob SquarePants is an American animated comedy television series created by marine science educator and animator Stephen Hillenburg for Nickelodeon. It first aired as a sneak peek after the 1999 Kids' Choice Awards on May 1, 1999, and officially premiered on July 17, 1999. It chronicles the adventures of SpongeBob SquarePants and his aquatic friends in the underwater city of Bikini Bottom.

Many of the series' ideas originated in The Intertidal Zone, an unpublished educational comic book Hillenburg created in 1989 to teach his students about undersea life. Hillenburg joined Nickelodeon in 1992 as an artist on Rocko's Modern Life. After Rocko was cancelled in 1996, he began developing SpongeBob SquarePants into a television series, and in 1997, a seven-minute pilot was pitched to Nickelodeon. The network's executives wanted SpongeBob to be a child in school, but Hillenburg preferred SpongeBob to be an adult character. He was prepared to abandon the series, but compromised by creating Mrs. Puff and her boating school so SpongeBob could attend school as an adult.

The series immediately became popular since its premiere in 1999, becoming the highest-rated and most viewed animated Saturday morning program that year, beating Pokémon. It has received worldwide critical acclaim for its humor, art style, characters, writing, and music, though it has also been criticized for its perceived decline in quality since its fourth season. As of 2025, the series is the fourth longest-running American animated series and the longest-running American children's animated series, surpassing Arthur in 2025. The series has run for a total of fourteen seasons, and in September 2023, was renewed for a fifteenth season, which premiered in July 2024.

The series' popularity made it a multimedia franchise, the highest rated Nickelodeon series, and the most profitable intellectual property for Paramount Consumer Products. By 2019, it had generated over $13 billion in merchandising revenue. Since its debut, it has inspired three theatrical feature films (starting with the first in 2004, The SpongeBob SquarePants Movie), two feature films for streaming, a Broadway musical, a comic book series, and video games. Two spin-off series, Kamp Koral: SpongeBob's Under Years and The Patrick Star Show, premiered in 2021.

SpongeBob SquarePants has won a variety of awards including six Annie Awards, eight Golden Reel Awards, four Emmy Awards, two BAFTA Children's Awards, and a record-breaking twenty-one Kids' Choice Awards. The series is also noted as a cultural touchstone of Millennials and Generation Z.