This genus and species first appeared in the 1986 Master's dissertation of Ouyang, but this is not considered formal publication under the International Code of Zoological Nomenclature. Ouyang subsequently published the scientific description of the genus and its type species in 1989 in a short paper (in Chinese) in a poorly distributed Zigong Dinosaur Museum newsletter,  so the author and date of these taxa is taken from there.

The type skull of Abrosaurus gigantorhinus (meaning "giant snout") was illustrated  in a photograph in one of those guidebooks, under the name Abrosaurus dongpoensis. Zhang and Chen (1996) provided a formal description of the genus, based on an unpublished description that appeared in the Master's dissertion of Ouyang in 1986.

They referred the genus to Camarasauridae.Zhang & Chen (1996) redescribed the genus (in English) with type species Abrosaurus gigantorhinus,  attributing this species to Ouyang's Master's dissertation as Ouyang, 1986, but since a dissertation is not a publication, their species A. gigantorhinus becomes a junior objective synonym of A. dongpoensis (it is based on the same type specimen).

Abrosaurus had a bulky body, column-like legs, and a small head with a nasal crest; the nostrils were almost above the eyes.