Gamma rays are electromagnetic radiation like x-rays and are the most energetic form ofrnelectromagnetic radiation with a very short wave length. theoretically i have measuredrnthe energy of interacted gamma rays using the NaI(Tl) and semiconductor detectors.rnThe interaction and detection mechanism ,resolution of detector, detector e ciency forrngamma measurement play greate role in increasing and decreasing the magnitude of thernradiation energy .Gamma energy is proportional to the deposited energy by the photornelectric ,compton and pair production interactions