Abstract: Based on damage mechanics model of one-dimensional mechanical and electrical couple of coal and rock，the damage mechanics model of three-dimensional mechanical and electrical couple of coal and rock is setup.Using the model，the relationship among electromagnetic radiation pulses，the amplitude and stress is analyzed.The effects of electromagnetic radiation and stress impacted by confining pressure conditions of the internal structure of coal and rock are simulated.Finally，the electro-magnetic radiation characteristics of sudden unloading uniaxial compression are analyzed.Application of research results show that: the model is reliable and advanced to analyze the characteristics of damage mechanics of coal and rock.  

Key words: Coal petrology, Mechanical and electrical coupling, Damage mechanics, Model