Objective:To explore the association between salivary galectin-3(Gal-3)and periodontitis stage.Methods:For this cross-sectional study,35 patients for each periodontitis Stage Ⅰ,Ⅱ and Ⅲ group were recruited,and 35 periodontally healthy subjects were included in the control group.Salivary level of Gal-3 was examined by ELISA.The association between Gal-3 and periodontitis stage was analyzed.Results:The median levels(M(Q1,Q3),ng/mL]of salivary Gal-3 in the healthy control group and the peri-odontitis Stage Ⅰ,Ⅱ and Ⅲ groups were 89.40(84.56,96.58),98.26(89.15,112.29),136.22(116.21,144.33)and 183.27(161.45,196.92),respectively.Jonckheere-Terpstra trend test showed that there was a sequential effect between salivary Gal-3 level and the stage of periodontitis(Z=10.178,Ptrend＜0.001).Spearman's rank correlation analysis showed that the level of Gal-3 was posi-tively correlated with PD,CAL,BI,BOP and PLI respectively(P＜0.001).Multinomial logistic regression analysis showed that Gal-3 level was significantly associated with periodontitis Stage Ⅰ,Ⅱ and Ⅲ,the adjusted odds ratio(aOR)were 1.061(95％CI:1.016-1.108,P=0.008),1.181(95％CI:1.105-1.202,P＜0.001)and 1.267(95％CI:1.177-1.365,P＜0.001),respectively.ROC curves showed that the AUCs of Gal-3 in the predicting stage Ⅰ,Ⅱ and Ⅲ periodontitis were 0.685(95％CI:0.167-0.524,P=0.005),0.958(95％CI:0.167-0.524,P＜0.001)and 0.997(95％CI:0.942-1.000,P＜0.001),respectively.Conclusion:Salivary Gal-3 level is significantly correlated with periodontitis stage,and it might be a potential biological marker for predicting peri-odontitis severity.