Understanding the thermal requirements and tendencies of the Chesapeake Logperch, Percina bimaculata, is critical for their effect management. Researchers proposed to determine the temperature preference of larvae, juveniles, and adults, as a surrogate for lethal temperatures. Temperature preference was higher than the acclimation temperature for both the adults and the adults acclimated to 5 mg/l salinity for all acclimation temperatures. At the highest acclimation temperature (25°C) the mean preferred temperature for adults was 26.8 and that for the adults acclimated to 25 mg/l salinity was 27.9. These preferred temperatures support our conclusion that the upper lethal limit of adults was between 25°--30°C, since fishes lost equilibrium, and some died when we attempted to acclimate them to 30°C