The cancer rate in India has more than doubled over the last 26 years. As per the Indian Council of Medical Research (ICMR) data, India had 14 lakh cancer patients in 2016 and this number is expected to increase. A machine is used to aim high-energy rays or beams from outside the body into the tumor. The machine most commonly used is called a linear accelerator or “linac.” In this paper Shielding thickness calculation for 6 Megavoltage Radiation from accelerator will be carried out based on the ICRP (International Council for Radiation Protection) recommendation. Additional shielding materials, their thickness will be assessed.