The visual function of 26 patients with a diagnosis of primary infantile glaucoma was studied. Quantitative visual acuities were determined in 15 patients. Sixteen eyes in these patients achieved 20/20 to 20/50 visual acuity and five additional eyes had 20/60 to 20/200. Thirteen eyes in young patients were noted to have central and steady fixation and four eyes exhibited eccentric fixation. Seven eyes were considered to have decreased visual acuity on the basis of anatomical defects. The remainder of the patients had decreased visual acuities secondary to amblyopia or large refractive errors. Amblyopia responded to treatment in six of 12 patients.