Abstract: This paper selects typical of hard and soft field coal sample,using the new Sansi computer controlled servo pressure machine for uniaxial compression tests to study the strength and deformation characteristics in the mode of loading coal,found the relationship of lateral strain and the rupture mechanism during compression of coal.The result of comparative experimental show that the coal samples presented very weak micro-seismic signal before the main rupture occurred that the damage occurred before the main band broadening,amplitude,maximum stress,the signal frequency become the most complex.This means that coal has entered a dangerous phase in this state,so it must take the appropriate measures.