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We have presented our results for the migration of Cs-137, in Venezuelan soils. This was accomplished by measuring the Cs-137 activity in soil samples taken between different soil revels from the surface to 100 cm by gamma-ray spectroscopy with a hype-pure germanium detector. Profiles were taken in the different types of areas. grass, arid tropical forest and the. rainforest, some of which are also cloud forest. Our measurements have shown that in various cases, there was more than 20% and up to 35% of the Cs-137 migrating below the 20 cm soil level. These results are conflicting with the general principle that 80-90% of the Cs-137 is retained in the upper 20 cm soil layer, but are consistent with a recent study of Brazilian soils. A possible explanation will be discussed.