Although tachinids are one of the most diverse families of Diptera and represent the largest group of nonhymenopteran parasitoids, their local diversity and distribution patterns of most species in the family are poorly known. In this study, 2 yr of samples from a Malaise trap were used to analyze the local richness and temporal distribution of a tachinid community in southwestern Ohio. In total, 883 tachinid specimens were collected, consisting of 117 species belonging to 69 genera. The majority of the specimens were collected in fall, followed by summer and spring, with 67, 22, and 11%, respectively. Estimated rarefaction curves indicate a predicted species richness of 217 species and suggest that we have sampled only a fraction of the diversity of Tachinidae occurring at this particular site. The species recorded in this study represent 16 and 19% of the species that are likely to occur in the northeastern United States and Ohio, respectively. In North America, there have been few, if any, previous attempts to quantify the diversity of tachinids on a local scale. Our results provide a baseline for understanding the temporal and spatial diversity of these ecologically and agronomically important parasitoids.