One hundred and twenty-one white-tailed deer (Odocoileus virginianus) from 24 counties in 11 southeastern states were examined for muscleworm, Parelaphostrongylus andersoni, and meningeal worm, P. tenuis. Muscleworm was found in deer of 12 counties in Florida, Georgia, Louisiana, North Carolina, and South Carolina. Meningeal worm was recovered from deer in 10 counties of Arkansas, Georgia, Maryland, North Carolina, Virginia, and West Virginia. Concomitant infections with P. andersoni and P. tenuis occurred in deer of two counties in North Carolina. Future studies on the distribution of protostrongylid lungworms of white-tailed deer must be based on the location and identification of adult nematodes since first-stage larvae of Parelaphostrongylus are indistinguishable morphologically.