Linear and mass attenuation of 662 KeV gamma radiations from alcohol ethanol by dilute solution of para-nitro aniline (C6H6O2N2) studied for different concentrations. Mixture rule for theoretical calculation of attenuation coefficient is developed for the solution; our study explores the validity of the expected exponential absorption law for gamma radiation in solution and also provides an alternative method for direct determination of linear and mass attenuation coefficients of soluble compound in alcohol.