The inhibition effect of Lactobacillus paracasei (L.paracasei) ET-22 live bacteria, known for its efficacy in preventing dental caries, and postbiotic components (heat-inactivated bacteria and secretions) on Candida albicans was investigated. After evaluating the antioxidant capacity of L. paracasei ET-22 live bacteria and its postbiotic components and the inhibition rate of Candida albicans hyphae transformation, an oral candidiasis model of ICR mice was established by injection of immunosuppressants and application of Candida albicans. Before and after modeling, L. paracasei ET-22 live bacteria with a dose of 10⁹CFU/mL and corresponding postbiotic components were continuously administered through drinking water for 18d to study the effects of L. paracasei ET-22 on the morphology of mouse tongue tissue and the expression of inflammatory factors. At a concentration of 10⁹CFU/mL of L.paracasei ET-22 live bacteria, the live bacteria exhibited the highest inhibition rate of 37.84% against the budding of Candida albicans. The heat-inactivated bacteria and secretions in the postbiotic components showed inhibition rates of 17.50% and 28.00%, respectively. In animal models, after intervention with live bacteria and postbiotic components, the concentration of IFN-γ in the serum was significantly reduced. In the secretion group, the content of IFN-γ and TNF-α in the tongue tissue was significantly reduced, while in the live bacteria group, only TNF-α content was significantly reduced. The live bacteria and heat-inactivated bacteria groups showed a significant increase in the CCL20 chemokine content and the richness and diversity of coated tongue microbiota. The histopathological sections showed that the ET-22 live bacteria and secretion group significantly improved the looseness of the mouse tongue epithelium and inflammatory cell infiltration, and the heat-inactivated bacteria group had a positive effect on the shedding of papillae and tongue epithelium. The experimental results showed that ET-22 could regulate oral microbiota composition and inhibit harmful bacteria to oral through alleviating the inflammatory infiltration and metastasis of tongue tissue. The study indicated that ET-22 could decrease the risk of oral candidiasis and could be further developed for oral probiotic food with the function of oral health caring.