Sinogastromyzon is a genus of hillstream loaches in the family Gastromyzontidae (traditionally grouped with Balitoridae), native to fast, well-oxygenated mountain streams in China, Vietnam, Laos and Taiwan. The genus shares the hillstream loach body plan: a strongly flattened head and trunk, and paired pectoral and pelvic fins spread wide and fused along their margins into a broad, sucker-like disc that lets the fish cling flush to rock faces even in strong current. Most species stay small, in the 1.5–4 in range recorded in the atlas, and graze algae and biofilm off submerged stone with a small, ventrally positioned mouth.
Hillstream loaches are a devoted niche within the aquarium hobby, kept in cool, high-flow "biotope" setups built to mimic a rocky mountain stream, and Sinogastromyzon is one of the genera hobbyists reach for alongside the more common Pseudogastromyzon and Beaufortia — though fish sold under a species name are usually only loosely identified rather than confirmed. Conservation data lag badly here: eleven of the atlas's 22 species are Not Evaluated and five more Data Deficient, with only one each Endangered and Vulnerable formally assessed, so most of what would tell us how this genus is actually faring simply has not been gathered yet.