[Objectives] The radular morphology of four Pleurotomariidae species, i.e., Bayerotrochus teramachii, Mikadotrochus hirasei, M. salmianus, and Entemnotrochus rumphii from the East China Sea were examined by scanning electron microscopy (SEM). We provide clear SEM images of the radula of Pleurotomariidae to further discuss the application of radula to Pleurotomariidae taxonomy. [Methods] The shells were broken into pieces using a hammer, and the visceral mass was removed with a dissecting needle to obtain the internal tissue. The radula was removed using a knife and analyzed under an anatomical lens (CEWEI PXS9-T). Any remaining soft tissue was soaked in 10% NaOH for 4 h, until complete dissolution, following which they were cleaned using an ultrasonic cleaner (GT SONIC-D2) for 2 min, rinsed in distilled water, dried. Radula samples were mounted on sticky tabs, sputter-coated with gold, and imaged under low vacuum. The prepared samples were sputter-coated with gold, using a Cressington Sputter Coater 108auto, and analyzed using a scanning electron microscope (SEM; TESCAN Vega3). Cleaned radulae that haven't been used for SEM were mounted on a glass slide in water, covered with microscopic glass, and observed under a compound microscope (CEWEI PXS9-T). Radular teeth were photographed using a camera attached to the microscope. The portion of the radula that was not coated was observed using an optical microscope. [Results] The radula of Pleurotomariidae species is different from that of most gastropods, with six different types of teeth: rachidian tooth, inner lateral teeth, outer lateral teeth, sickle teeth, filament-tipped teeth and paddle-shaped teeth (Fig. 2). The four Pleurotomariidae species in this study all have 1 rachidian tooth, 2 or 3 inner lateral teeth, 20﹣25 outer lateral teeth, 16﹣32 sickle teeth, 35﹣62 filament-tipped teeth and 10﹣26 paddle-shaped teeth (Table 2). [Conclusion] The morphological differences of the radula are less within genera and greater between genera, which is mainly reflected in rachidian tooth, inner lateral teeth, and the cusps and bases of sickle teeth. The radula of E. rumphii has 26 vertical rows of paddle-shaped teeth, unlike the previous study which had 10 vertical rows. The transition between sickle teeth and filament-tipped teeth and filament-tipped teeth and paddle-shaped teeth are described in-depth, two criteria were proposed to help to determine the number of these three types of teeth.