To evaluate 20 different automated biopsy devices with respect to the quality of tissue obtained for histopathologic analysis, a total of 1,470 18-gauge biopsy specimens were obtained from 10 fresh autopsy cases, including 30 liver, 20 kidney, 10 pancreas, and 10 psoas muscle biopsy specimens per device and per biopsy depth. There was no statistical difference in the performance of the long-throw Biopty, ASAP 18, 1.9-cm UltraCut, long-throw Monopty, and 2.5-cm ABS biopsy guns. All obtained a large amount of tissue with minimal fragmentation or crush artifact. Most of the short-throw biopsy guns (depth of biopsy < or = 1.1 cm) did not perform as well. Although the other guns performed adequately, less than optimal results were obtained with the Temno, Bio-Gun, Roth, Klear Kut, ABC, and Urocut biopsy guns. Most 18-gauge automated biopsy devices with a biopsy excursion of at least 2.0 cm provide a high-quality, diagnostically adequate specimen for histopathologic analysis.