Although other subunits of MCM2–7 complex have been studied in tumors, such as MCM6 and MCM7, previous reporters only show MCM3 is a prognostic factor for various tumors, its function in tumor progression is reported rarely, especially in radioresistance generation, we first systematically studied the role of MCM3 in HCC radioresistance and the regulatory mechanisms. This evidence concerns the gene MCM2 and hepatocellular carcinoma.