Ikimonogakari (いきものがかり) is a Japanese pop rock duo from Kanagawa Prefecture, Japan consisting of Yoshiki Mizuno and Kiyoe Yoshioka. The group started in February 1999 with Hotaka Yamashita and Yoshiki Mizuno, who had known each other since they were six years old, and was joined by vocalist Kiyoe Yoshioka in November of the same year. The group's name is a reference to ikimono-gakari (いきものがかり), a group of children who are responsible for looking after plants and animals in Japanese elementary schools.

In 2006, the group released its first single on Sony Music Entertainment Japan's Epic Records label. Several of their albums have reached number one on the Oricon weekly rankings, and their songs have been featured on various media: from TV commercials, anime shows such as Naruto Shippuden, Japanese TV Dramas such as Women Won't Allow This (「女はそれを許さない」, "Onna wa Sore o Yurusanai"), live action movies such as Time Traveler: The Girl Who Leapt Through Time (2010) (『映画：時をかける少女』　（2010年）, "Eiga: Toki o Kakeru Shōjo (2010)"), the 2012 Olympic broadcast theme song for NHK, and the set piece for a national junior high music competition.

Their official fan club is named Ikimonogakari Fan Class 1-2 (いきものがかりファンクラス1年2組, , "Ikimonogakari Fan Kurasu 1-nen 2-kumi")

Mizuno has the most composed songs among them, while Yamashita ranks second. Yoshioka has contributed lyrics to a few songs, but Namida ga Kieru Nara is the only song on which the three of them have collaborated.

In June 2021, it was announced that Hotaka Yamashita was leaving the band which would continue as a duo.