Objective:To study the regulatory effects and mechanisms of miR-143-5p on cadmium-induced apoptosis in LLC-PK1 cells. Methods:Microarray analysis was performed to detect dysregulated expression of miRNAs caused by cadmium. Reliability of microarray analysis was validated by quantative real-time PCR. Over-expression and low expression of miR-143-5p were simulated by its mimic and inhibitor transient transfection with Lipofectamine 2000,and the effect was verified by qRT-PCR. Hoechst 33258 staining and AnnexinV-FITC/PI method were used to detect apoptosis. Target gene of miR-143-5p was validated by bioinformatics analysis,real-time PCR and Western blot. Western blot was performed to analyze the regulatory effect of miR-143-5p on apoptosis-related pathway. Results:The expression of miR-143-5p was up-regulated by cadmium (P < 0.01). Compared with the negative control(miR-NC)group,the expression of miR-143-5p was significantly up-regulated after miR-143-5p mimic and down-regulated by inhibitor transfection (P < 0.01). Over-expression of miR-143-5p markedly increased LLC-PK1 cells apoptosis(P < 0.01). The mRNA and protein levels of AKT3 were both targeted and regulated by miR-143-5p. Over-expression of miR-143-5p reduced protein levels of p-Akt and p-Bad and increased expression of caspase-9 and caspase-3. Conclusion:MiR-143-5p may promote cadmium-induced apoptosis via targeting AKT3 and inhibiting Akt/Bad signal pathway in LLC-PK1 cells.