OBJECTIVE: To investigate whether circular RNA circRSF1 regulates radiation-induced inflammatory phenotype of hepatic stellate cells (HSCs) by binding to HuR protein and repressing its function. METHODS: Human HSC cell line LX2 with HuR overexpression or knockdown was exposed to 8 Gy X-ray irradiation, and the changes in the expression of inflammatory factors (IL-1β, IL-6 and TNF-α) were detected by qRT-PCR. The expressions of IκBα and phosphorylation of NF-κB were detected with Western blotting. The binding of circRSF1 to HuR was verified by RNA pull-down assay and RNA-binding protein immunoprecipitation (RIP). The expressions of inflammatory factors, IκBα and the phosphorylation of NF-κB were detected after modifying the interaction between circRSF1 and HuR. RESULTS: < 0.05). CONCLUSION: circRSF1 reduces IκBα expression by binding to HuR to promote the activation of NF-κB pathway, thereby enhancing radiation- induced inflammatory phenotype of HSCs.