Planthoppers from Malaise traps (22 traps operated continuously over 3 years at 11 sites) were investigated as a component of an ongoing all-taxon biotic inventory of the Great Smoky Mountains National Park. The Malaise samples contained 2,195 specimens representing 55 species from 7 families. Elevation patterns and seasonality of planthoppers from the Malaise traps are also presented. Based on Malaise trap data, species accumulation curves and 9 estimators of species richness anticipated 57–81 species, a higher number than predicted in our previous study (Bartlett & Bowman 2004), but lower than the cumulative species list, currently including 97 species in 10 families based on 6,860 specimens. None of the data sets based on single sample methods produced estimates of species richness that were greater than the observed diversity from the compiled species list. Species richness estimates between 95–124 were obtained by combining the Malaise trap sample data with Bartlett and Bowman's (2004) sweep sample data and additional data from 2006, although two estimators still remained below the observed richness of 97 species for the Park. Implications of these findings are discussed.