Popotan (Japanese: ぽぽたん) is a Japanese adult visual novel developed by Petit Ferret with character designs by Akio Watanabe under the alias Poyoyon Rock. It was originally released as a PC game for CD-ROM on December 13, 2002, and subsequently re-released on DVD-ROM and for the PlayStation 2 with certain scenes removed. The title Popotan is a nonsensical word meant to reflect the prominence of dandelions, spelled tanpopo (たんぽぽ) in Japanese; Petit Ferret also produced a fan disc shortly before the DVD-ROM re-release. Popotan has been adapted to other media, including a novel series (Popotan～ Himitsu no Jumon～ Kōhen) by Sassami Yachiruda; a manga series by Yūjiro Izumi; a twelve episode anime television series directed by Shinichiro Kimura, animated by Shaft, and licensed in North America by Geneon USA and later, Sentai Filmworks; a radio drama (Poporaji); and several art and reference books.

Gameplay in Popotan follows a semi-predetermined plot; major events remain the same, but personal storylines can diverge from the player's choices. The game focuses on protagonist Chris, a drifter who meets three girls, the youngest of whom is 11 years old, and their maid in a mansion near the ruins of Tokyo in the distant future. The player's goal is to make available sexual scenes and images that the player can view or replay at any time, depicting the protagonist having sexual intercourse with one of the girls. The player can pursue other girls once they have finished one of the sisters' storylines.

Sales of the visual novel and its fan disc made the top 50 list of bestselling bishōjo games in Japan multiple times and it spawned the Internet meme "Caramelldansen" when the opening was put to sped-up music by the Swedish band Caramell. Reception of the anime has been mixed with those who reviewed the first volume critical of the anime's sexual themes, especially with regard to 11-year-old Mii, while those who reviewed the series as a whole have tended to give overall more positive reviews, praising the story's unexpected depth.