The meningeal worm (Parelaphostrongylus tenuis) was found in 75 of 190 (39%) white-tailed deer (Odocoileus virginianus) examined in Oklahoma from 1977-81. Infections were found in deer from southeastern mixed forest, oak-hickory forest, oak-bluestem parkland and oak-hickory parkland, and not in deer from western bluestem prairie, bluestem-grama prairie and grama-buffalo grass ecoregions. Factors which may influence the distribution of meningeal worm in Oklahoma include distribution and densities of suitable snail hosts and deer feeding habits.