【】Objective: Investigating the mechanism underlying the effect of intra-articular injection of ozone water on cartilage repair in KOA rats via the miR-214-3p/NF-κB signaling pathway, so as to Provide a theoretical basis for the clinical application of ozone water. Methods: Sixty male SD rats were randomly divided into blank group and experimental group. The experimental group was randomly divided into model group, ozone water treatment group, ozone water + no-load adeno-associated virus (AAV-NC) group and adeno-associated virus group with ozone water + miR-214-3p inhibitor (AAV-miR-214-3p inhibitor). After treatment, the articular cartilage repair status was evaluated by articular cartilage surface gross scoring, HE staining, and modified Mankin"s score; the expression levels of IL-1β, TNF-α, and MMP-13 were detected by ELISA; the protein expression levels of IKKβ, p65, and p-IκBα were detected in cartilage tissues of each group by Western blot ; Real-time PCR (RT-PCR) gene expression of IKKβ, p65, IκBα and miR-214-3p. Results: compared with the blank group, the remaining groups of rats showed different degrees of cartilage damage, and the scores of the ozonated water treatment group and the ozonated water+AAV-NC group were significantly lower compared with those of the ozonated water+AAV-miR-214-3p inhibitor group (P<0.05); ELISA results: the ozonated water treatment group and the ozonated water+AAV-NC group showed significantly lower (P<0.05) scores in IL-1β, TNF-α and MMP-13 contents were significantly lower in the cartilage tissues of rats in the ozonated water treatment group and the ozonated water+AAV-miR-214-3p inhibitor group compared to the model group and the ozonated water+AAV-miR-214-3p inhibitor group (P<0.05); RT-PCR results: in the cartilage tissues of rats in the ozonated water treatment group and the ozonated water+AAV-NC group compared to the model group and the ozonated water+AAV-NC group The mRNA expression levels of IKKβ and p65 were significantly down-regulated, while the mRNA of IκBα was significantly up-regulated (P<0.05).Western blot showed that, compared with the model group and the ozonated water+AAV-miR-214-3p inhibitor group, the rat cartilage tissues in the ozonated water treatment group and the ozonated water+AAV-NC group showed IKKβ, p65 and p-IκBα protein expression levels showed significant down-regulation, on the contrary, IκBα protein expression levels showed up-regulation (P<0.05).Conclusion: Ozone hydrotherapy significantly ameliorated cartilage damage in KOA rats, and its mechanism of action may be related to inhibiting the activation of the NF-κB signalling pathway through up-regulation of miR-214-3p expression and promoting cartilage repair in KOA rats.