Through detecting support setting load， cycle ending resistance， time-weighted average working resistance and its distribution frequency of 8120 fully mechanized experiment working face in Xiadian Mine， the fully mechanized caving face mine pressure behavior law was summarized. The result showed that working face average period roof weighting step was 21.6 m， average dynamic load coefficient was 1.67， the release of fully mechanized caving face top coal led face width upper top coal broken and move and lowered support setting load and the time-weighted average working resistance.