Abstract: The shielding calculation and design modification work were performed for a 1.5 MeV electron irradiation platform of 15 kW. Based on the structure of irradiation platform, a three-dimensional model was constructed for shielding calculation using Monte Carlo code. The shielding ability of the walls was evaluated through calculation, and it is found that the design meets requirements. The shielding structure of the irradiation chamber and the door was determined based on the comparison of different shielding calculation results. Measurements were carried out to verify the calculation results at the end of project phase. The measured results show that the wall and new shielding structure provide proper shielding, which reduces the photon dose rate below the design goal.