In this paper

the MCNP code is used to calculate neutron transmission through various materials of 1–40 cm thickness in energy range of 0.025 eV to 20 MeV.The materials are principal shielding materials of PE

water

concrete

Fe

Cu

Pb and PE/BC4composite

and the additives of B4C and Gd2O3.The following results were obtained:(1) the neutron transmission decreased with increasing thicknesses of a material;(2) for a certain material

with decreasing energy of the neutrons

the neutron transmission decreased faster

except PE and water

where the neutron transmision keeps almost the same in the entire energy range;and(3) for low energy neutrons

the differences of transmission decreasing trend with the increasing thicknesses for different materials were significant

whereas for high energy neutron

the decreasing trend was not distinct.A combination of a main material with an additives can achieve better shielding effect.