OBJECTIVES: This study proposes a novel approach, "Low-energy photon Lipiodol-Enhanced Radiotherapy" (LEPERT), for patients with liver cancer. Moreover, we evaluate the dose difference of the conventional treatment planning with 10 MV X-ray beam (MV-plan) and LEPERT. METHODS: The computed tomography (CT) was modeled with the Monte Carlo simulation. For LEPERT, 120 kV X-ray beams collimated with CT were irradiated on a virtual tumor filled with Lipiodol at 10-50 mg/mL, which was inserted into a whole-body phantom. A prescribed dose of 40 Gy/4fr was irradiated to achieve D RESULTS: Differences in the effective energy and off-axis ratio between the measurements and simulations were within 2 keV and 3%, respectively. The D CONCLUSION: The LEPERT can selectively enhanced only the tumor region with sparing the OAR dose. It could be a novel and effective treatment technique in the point that the treatment machine is a general CT device.