To define ocular abnormalities in mice with autoimmune disease, we performed biomicroscopic examinations and examined ocular tissue in MRL/l, MRL/n, NZB, NZB/NZW, and Palmerston North mice. Results were compared with MRL/Mp--lpr/lpr, C57BL/6J--lpr/lpr, and normal control strains. Eighty-seven percent of MRL/l and MRL/n mice had typical band keratopathy; this was confirmed by histologic examination. Posterior uveitis was found in 35% of adult MRL/l mice. MRL substrains are potentially important models of ocular disease.