In Japanese folklore, the tsuchinoko (ツチノコ or 槌の子), literally translating to "child of hammer", is a snake-like being. The name tsuchinoko is prevalent in Western Japan, including Kansai and Shikoku; the creature is known as bachi hebi (バチヘビ) in Northeastern Japan.

Tsuchinoko are described as being between 30 and 80 centimetres (12 and 31 inches) in length, similar in appearance to a snake, but with a central girth that is much wider than its head or tail, and as having fangs and venom similar to that of a viper. Some accounts also describe the tsuchinoko as being able to jump up to 1 metre (3.3 feet) in distance followed immediately by a second jump while still in the air.

According to legend, some tsuchinoko have the ability to speak and a propensity for lying, and they are also said to have a taste for alcohol. Legend records that it will sometimes swallow its own tail so that it can roll like a wheel, similarly to the "hoop snake" of American legend.