Kecleon is a bipedal, reptilian Pokémon that is usually green. On either sides of its head are yellow frills, which are connected by lines to its yellow lips and rings around its eyes. There are small ridges on its shoulders and a red zigzag stripe around its midsection. The hands and feet have three short digits each, and it has yellow soles. It also has a long skinny tail that is usually curled tightly in a spiral.
Kecleon is able to change the colors of its body at will, and is known for frequently using this ability to camouflage itself. However, it is unable to change the color of its red stripe. By using camouflage to appear almost invisible, it can sneak up on prey and ensnare it with its long pink tongue. A purplish variant has been seen in the anime and the Pokémon Mystery Dungeon series; whether this is an example of it changing color or simply a different kind of Kecleon is unknown. This Pokémon lives in forests.