Abstract: Based on "short term clogging test procedure" in ISO clogging test methods for drip emitters, 15 kinds of dental labyrinth drip emitters from home and abroad were tested for anti-clogging ability. The results show that single structure parameters (width and depth of flow path/passage, and height, and angle of dentations) are local and difficult to represent the anti-clogging ability of emitters. Characteristic structure parameters(minimum size of cross section, hydraulic radius and dentitions spacing) can represent the anti-clogging ability of emitters in a sense. There are anti-clogging critical values under the test. Rated flow Qr and the ratio of diameter of labyrinth passage to diameter of particle η are well cor related to the anti-clogging ability and have anti-clogging critical values too. The emitters are easy to be clogged and the anti-clogging ability increases with the increase of characteristic structure parameters, rated flow and the ratio of diameter of labyrinth passage to diameter of particle when the parameters are less than the critical values. Contrariwise, the emitters have stronger anti-clogging ability. The anti-clogging ability is no longer sensitive to the increase of the parameters. The research results provide references for optimization design of dental labyrinth drip emitters.