Chinchou is a small, fishlike Pokémon with a round, blue body. It has large yellow eyes with pupils shaped like plus signs, a pair of semi-transparent, light blue pectoral fins, and stubby feet. Positioned on Chinchou's rear, where its tail would be, are a pair of antennae that curve up and over its head. The antennae developed from fins and have yellow, teardrop-shaped orbs at the tips.
Prey is lured toward Chinchou by the soft glow from the orbs on its antennae. It also flashes its light to communicate with others of its kind and claim territory. Inside the antennae are electricity-generating cells that create so much electrical power that they even make Chinchou tingle slightly. By discharging positive and negative electricity, it can both defend itself and stun its prey. Chinchou lives on dark ocean floors, rarely ever coming up to the surface. However, it has demonstrated the ability to walk on land in the anime.
Multiple Chinchou made their main series debut in Takin' it on the Chinchou, all under the ownership of Dayton, with one of them being nicknamed Bright. They were featured as subjects of the Parade of the Chinchou, which celebrated the natural migration of newly-hatched Chinchou from the mountains to the ocean.
Chinchou, the Angler Pokémon, have the ability to conduct electrical currents from their two tentacles, which flow positive from one end and negative from the other. Chinchou can also communicate underwater by flashing its tentacles.
In Teddiursa's Picnic, a Chinchou appeared in its Poké Ball after a wild Granbull had spit out all of the Poké Balls that it stole to get attention on its dislocated jaw. It was later returned to its owner by Wilton afterwards.
Pokémon Pinball: Ruby & Sapphire: Chinchou are the main bumpers on the Ruby Field. Hitting a nearby button will change the formation from three floating in place, to three moving around, to just the one moving around. They will occasionally disappear and be replaced by Lotad or Whiscash.
This Pokémon was unavailable prior to Generation II.