We cared for two patients with longstanding vernal keratoconjunctivitis who had bacterial corneal ulcers in each eye. Both patients were young, black, and had histories of atopy. The patients came for treatment with acute symptoms of pain, redness, and reduced vision in the affected eye. On examination in each case we found an epithelial defect associated with dense stromal infiltration, a calcific plaque in the bed of the ulcer, and a severe anterior chamber reaction, including a hypopyon in two cases. Cultures of corneal scrapings from all four eyes were positive for Staphylococcus aureus, and three of the four infections were polymicrobial. All four eyes responded rapidly to intensive topical antibiotic therapy, debridement of the calcific plaque, and subsequent treatment with topical corticosteroids and/or cromolyn sodium. Bacterial keratitis can occur in patients with vernal keratoconjunctivitis, especially those with vernal corneal ulcers. The abnormalities of ocular immune mechanisms found in patients with vernal keratoconjunctivitis may predispose them to bacterial keratitis.