The Hillstream loaches are a family (Balitoridae) of small Eurasian fish. Most species are rheophilic, living in swift, clear and well-oxygenated streams. Several species of the subfamily Balitorinae live in fast-flowing streams or torrents and have a large sucker mouth and modified ventral fins used for clinging to rocks. They have a number of similarities with the sibling family of loaches (Cobitidae), such as multiple barbels around the mouth. They should not be confused with the loricariids, which looks similar but is a family of catfish.
The family includes over 600 species in more than 60 genera. Many of the species are popular for aquaria.