The ileofibularis muscle of the turtle Trionyx sinensis was examined by light and electron microscopy. Acetylcholinesterase staining showed an "en grappe" type of terminal. The muscle showed succinic dehydrogenase activity with three different types of fibers. The fibers appeared fibrillar type under the electron microscope. Neuromuscular junctions showed the presynaptic portion containing clear vesicles and mitochondria, whereas the postjunctional portion showed only few junctional folds.