Hanako (Japanese: 花子) (purportedly c. 1751 – July 7, 1977) was a scarlet koi fish reportedly owned by several individuals, the last of whom was Komei Koshihara.

She was reported to be the longest-lived koi fish ever recorded, having died at the age of 226, although there is dispute as to the veracity of her longevity.

[1] Far exceeding the average lifespan for koi, she was reportedly 226 years old at the time of her death.

At this time, Hanako weighed 7.5 kg (17 lb) and measured 70 cm (28 in) in length.

[3] In July 1974, a study of the growth rings of one of the koi's scales reported that Hanako was 226 years old.