[en] Attenuation characteristics for the fission neutron by various shielding materials have been studied for testing data and methods. Attenuation curves were determined for six kinds of hydrogenous material, seven sorts of concrete, and three kinds of metal under the condition of a narrow beam geometry. Transmission curves were obtained over the two decades of exponential decrease. They indicated in logarithmic expression to be more downward concave, compared with the single exponential attenuation for the all materials used in this study. A dose equivalent of neutrons through the shielding material may be represented by the following: Dsub(t) = Dsub(o) exp [-T/lambdasub(eff)] where Dsub(o) and Dsub(t) are dose equivalents at O cm and T cm thickness of the shielding materials, respectively, lambdasub(eff) is a relaxation length which depends on absorber materials and their thickness. A convenient approximation to the relaxation length is given by lambdasub(eff) = lambdasub(o) + α.T where lambdasub(o) and α were determined from the experimental results. (author)