Abstract: The tegumental surface of the mainland strain of adult Schistosoma japonicum prepared by the CO2 critical point drying method was studied using scanning electron microscopy, in the depth of the oral sucker numerous silk-like villi were observed. At least three types of spines could be seen on the inner surface of both oral and ventral suckers. There were four types of bosses present on the tegument surface in the form of papilles, discoids, hillocks and balls with the former two types predominating. Papilla-like bosses are mainly distributed on the inner and outer edges of oral and ventral suckers, neck region and dorsal as well as ventral surfaces, while discoid-like bosses could be detected mainly on dorsal and ventral surfaces, neck region and inner surface of gynecophoric canal of male worms. They were probably sensory organelles according to some authors. Spines covering the inner surface of gynecophoric canal are sharp and knife-like but obtuse at their bases. Spines could also be found in neck region of the worms, but much less in male worms than in females. Numerous pores could be seen on the tegumental surface of the worms. It is worth noting that difference in fine details of the tegumental ultrastructure of adult Schistosoma japonicum from different reports may be of technical reasons. The technique hereby reported seems to be more suitable for scanning electron microscopy so as to avoid distortion in preparing living specimens.