The three species of the difficult Hydropsyche instabilis-group described by F. Schmid (1952) from the Iberian peninsula are revised, based on the types. H. hibera proved to be a synonym of H. instabilis (Curtis); H. infernale (here emended to infernalis) and H. ambigua (originally described as dubia) are good species, the first apparently closely related to H. siltalai Döhler, the second extremely near to H. tenuis Navas. Notes on the known distribution in Spain of the three species are added ( H. instabilis and H. ambigua are widely distributed; H. infernalis is known from the Sierra Nevada only).