When comparative method is adopted in gamma-ray spectrometry measurements of environmental samples

self-attenuation correction of under test samples is necessary

because of different self-attenuation coefficients of the reference and test samples.In this work

we investigate the self-attenuation correction by finding the relationship between the transmissivity and self-attenuation at the same photo-peak.The parameters of HPGe detector crystal were obtained by point source experiments.Based on these parameters

the relationship between the transmissivity and self-attenuation were studied by using the MCNP code.The differences of density and chemical composition were taken into account.This results show that method can be used to estimate the self-attenuation correction of complicated matrix samples.