The lungworm, Dictyocaulus viviparus, was found in 240 (29.8%) of 806 white-tailed deer collected in Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, South Carolina, Texas, Virginia, and West Virginia. The infection was not found in deer of Tennessee and St. Croix of the U.S. Virgin Islands. Lungworm infections varied significantly with season of collection, age, and sex of the host.