What's New, Scooby-Doo? is an American animated television series produced by Warner Bros. Animation for Kids' WB. It is the ninth incarnation of the Scooby-Doo franchise that began with Scooby-Doo, Where Are You! and the first Scooby-Doo series in a decade (since A Pup Named Scooby-Doo ended in 1991). It is also the first Scooby Doo series to be produced by Warner Bros. Animation, and the first since both the foreclosure of Hanna-Barbera and William Hanna's death in 2001.

The show follows the format of Scooby-Doo, Where Are You!, in which Scooby-Doo, and his companions Fred, Daphne, Velma, and Shaggy, travel to varying locations solving mysteries; this format is modernized for What's New, Scooby-Doo?, in which the characters utilize technology that did not exist at the time Scooby-Doo, Where Are You! first aired. The series marked the return of Velma and Fred as main characters in the regular Scooby-Doo franchise since 1984's The New Scooby-Doo Mysteries. 1988's A Pup Named Scooby-Doo (which also featured Velma and Fred) was a prequel to the original 1969 series Scooby-Doo, Where Are You!.

It is the first television series in the franchise in which Frank Welker, Grey DeLisle, and Mindy Cohn respectively portrayed the voices of Scooby-Doo, Daphne, and Velma. Welker also returns as Fred in the series. Casey Kasem returned to voice Shaggy on the show after five years of not voicing him. This was the final Scooby-Doo series where Kasem voices Shaggy before the actor's death in 2014, though he still voiced other roles in the two following series, Shaggy & Scooby-Doo Get a Clue! and Scooby-Doo! Mystery Incorporated. This is the first Scooby-Doo series where Scooby is not voiced by his original voice actor Don Messick who died in 1997.

The series premiered on September 14, 2002, and ran for three seasons before ending on July 21, 2006. The title song was performed by Canadian band Simple Plan. Reruns of the series have aired on both Cartoon Network from 2003–2016 and Boomerang from 2006–2020 and since 2023 in the United States. It also aired on Teletoon in Canada, and CBBC in the UK, then CITV.

In 2019, the show was made available to stream on Netflix in the US. In 2021, the rights were turned over to HBO Max.