In view of the defect of the traditional measurements of materials linear absorption coefficients, in this work the linear absorption coefficients of gamma ray in different experimental conditions are simulated and calculated using the Monte Carlo N Particle Transport Code (MCNP) and the method of full energy peak area, and the deviations of the coefficients from the recognized values are also calculated. The appropriate experimental condition is obtained by reducing the deviation to a reasonable scope and contrasting with other methods. As a result, the approved measuring equipment which is easy to adjust is able to obtain the information about radiation energy. It offers a better accuracy and higher detection efficiency compared with the counting method.
