Abstract: The holodiameter full-simulation blow-down exploitation experiment was done under the conditions of 75MPa of overburden pressure, 120℃ of formation temperature, 30MPa of formation pressure and water saturability.The results revealed that in fracture-pore dual media, the increase of production pressure drop resulted in the increase of effective overburden pressure and the decrease of fracture height, which caused the demage of gas permeability in reservoirs.It was showed that the higher the permeability was, the greater the damage of permeability was.On this basis, the critical production pressure drops for different types of reservoirs were suggested.