Twenty-four eyes removed for complications of HSV keratitis were studied histopathologically. There were 20 men and 4 women with an average age of 61 years. Severe keratitis was seen in 11, moderate in 7, and mild in 3 eyes. Common features associated with severe keratitis were: acute perforation, granulomatous keratitis with giant cells in the stroma and Descemet's region, stromal inflammatory cells, angle-closure, severe iridocyclitis with diffuse or focal infiltration of lymphocytes and plasma cells, low-grade vitritis, choroiditis, and/or retinal periphlebitis. Specimens with moderate to mild keratitis had a similar distribution of inflammation but a lower incidence of granulomatous keratitis.