Abstract：The increasing and dissipation regularity of the pore water pressure with depth and broadness under the different hammering energy of the downstream alluvial and diluvium soil of Yellow River is studied by experiment. The experiment results show that increasing and dissipation rate of the pore water pressure under the action of hammering energy of the alluvial and diluvium soil of Yellow River is comparatively high. The influence depth and width of the hammering energy are of the tendency in direct proportion with the magnitude of the hammering energy. This kind of soil is suitable for being compacted by the method of dynamic compaction. The stratum of this area is mainly composed of silty clay，and the increasing and dissipation of the pore water pressure are relativity slow below the groundwater level，under the hammering energy. The recovery of the soil strength will need more time. During the application of dynamic compaction method，the low energy and long resting time method should be considered.
