Aggretsuko, also known by its Japanese title Aggressive Retsuko (Japanese: アグレッシブ烈子, Hepburn: Aguresshibu Retsuko), is a Japanese–American animated anime comedy television series based on the eponymous character created by "Yeti" for the mascot company Sanrio. The character first appeared in a series of animated shorts by Fanworks which aired on TBS Television between April 2016 and March 2018.

An original net animation (ONA) anime series adaptation was launched worldwide on Netflix in April 2018, followed by a second season in June 2019, a third season in August 2020 and a fourth season in December 2021. A fifth and final season debuted in February 2023.

A comic book series adaptation by Daniel Barnes and D.J. Kirkland was launched by Oni Press. The first issue was released on February 5, 2020.

A mobile game, Aggretsuko: The Short Timer Strikes Back, was released by Hive for Android and iOS in July 2020. The game, which is available worldwide, includes the full 100 short episode series, which need to be unlocked individually via normal gameplay. Whilst subtitled, the short episodes were not dubbed into other languages. The main character Retsuko was included in Hello Kitty Island Adventure on Apple Arcade in June 2023 as a major character.