Influence of soil particles and organic matter on distribution of 137Cs and relationship between 137Cs and organic matter in the Loess Plateau were studied. The results showed that depth distribution pattern of 137Cs wasn't consistent with that of soil particles

only similar to that of certain size soil particles within the surface several centimeters soil. Depth distribution pattern of 137Cs and organic matter depended on the land use. 137Cs and or ganic matter were enriched in the top of soil profile in uncultivated soils. However

depth distribution pattern of 137 Cs and organic matter exhibited uniform pattern in cultivated soils as a result of tillage operation. The relationship between 137Cs and organic carbon was significant at the 0. 01 level with the correlation coefficient of 0. 791.