Asian water dragons are typically bright green. Their laterally flattened tails have brown bands and end in a fine point. They use their tails for balance and leverage when climbing, and can whip them to defend against predators. High horn scales run from the dragon's head, down the back and to the base of the tail. Water dragons are sexually dimporphic, with males generally exhibiting more vivid colors. Males have an area under the throat that is intensely orange to yellow with pink tones in the lower jaw. They also develop larger heads, jowls and crests on the back and neck, and their femoral pores are somewhat larger than a female's.
Water dragons do not have a typical dewlap or throat pouch. The species has well-developed legs, the front legs generally more slender than the back. Each leg is five-toed with long, thick claws ending in sharp, needle-like points. The water dragon's clawed front legs help it climb and grasp branches. Its muscular back legs also aid in climbing, as well as swimming and jumping or leaping from object to object. Water dragons can also run bipedally.
When nervous or frightened, Asian water dragons seek refuge in the water. They are strong swimmers and, if necessary, can remain submerged for long periods of time—sometimes as long as 25 minutes!
Asian water dragons have not been assessed by the International Union for Conservation of Nature. Threats to the species have not been identified, though they are commonly found in the pet trade. Habitat destruction is also common within their native range. Asian water dragons have been identified as an invasive species in Hong Kong, likely due to the release of unwanted pets.