Aluterus scriptus is a medium size fish which can grow up to 110 cm in length. The body shape looks like an elongated oval, strongly compressed. Its background body coloration is olive-brown or grey depending on its surrounding environment, irregular blue lines and spots are distributed on the body mixed with some black spots mainly on the head. The mouth is small and at the end of its pointed snout. Like all the Tetraodontiformes, it has no pelvic fin but has two particular dorsal spines; the first anterior one is long, slender and erectile, located just over the eyes, the second is small and not easy to see but it locks the first one when it is erected. The rounded caudal fin is quite long and can be displayed as a fan. The juveniles have a yellow with black spots body coloration.