The anatomy and microscopic structure of the central nervous system(CNS) of Neverita didyma are preliminarily described.The CNS includes paired cerebral ganglia,pedal ganglia,pleural ganglia,and unpaired visceral ganglion.Every ganglion is composed of a surrounding sheath,a cell body region and a neuropile region.The N.didyma has a short commissure between the left and right cerebral ganglia as well as the left and right pedal ganglia. A short connective between cerebral-pleural,cerebral-pedal or pleural-pedal ganglia is also observed.The distribution of neurons in pedal ganglia shows zonation obviously.