We present new state records for 3 crayfish species in the Tennessee River basin in Mississippi, and the first drainage-specific distributional information in the state for a fourth. The species—Cambarus girardianus, Cambarus rusticiformis, Orconectes spinosus, and Orconectes wright,—are all known from the Tennessee River basin in Tennessee, while all but O. wrighti are also known from Alabama. We also expand the distribution of Procambarus viaeviridis in the state to include the Tennessee River drainage in Alcorn and Tishomingo counties, MS. We briefly discuss taxonomic issues involving C. girardianus and O. spinosus. Based on their distributions in neighboring states, we suspect that several other species may occur in the Mississippi portion of the basin.