The spotless smooth-hound (Mustelus griseus) is a species of houndshark, in the family Triakidae, found on the continental shelves of the northwest Pacific, between latitudes 40° N and 11° N, from the surface to a depth of 300 m. It can grow to a length of up to 1 m (3 ft 3 in).

Both the dorsal fins have a curved trailing edge and the distance separating them occupies about 20% of the total length of the fish.

[2] The spotless smooth-hound is found in the temperate and tropical Pacific Ocean between 40°N and 11°N, off the coast of Vietnam, Japan, China and Taiwan, and possibly the Philippines.

It is found near the seabed, often over sandy substrates and is thought to feed on crustaceans and other benthic invertebrates.

The IUCN has listed its conservation status of this shark as being "endangered" and considers that further survey work needs to be done to assess population trends and catch sizes.