Abstract: In order to keep long stability of deep chamber,reduce the maintenance cost of chamber and ensure the safety production of mine,take the second large par t cross section drive head chamber in blind shaft of Xinzhuang Mine as engineering background,numerical calculation was applied to study pressure- relief mechanism of「 oof pressure- relief roadway for large cross section chamber. The study results showed that after roof pressure- relief,the plumb stress of surrounding rock in roof and floor of chamber was sharply reduced both,but the plumb stress of floor was reduced sharplyer than roof. The roof pressure- relief would have less interference to roof of chamb er.After pressure- relief,the horizontal stress and horizontal displacement of roof, floor and two sides surrounding rock of chamber were obviously reduced and therefore pre ssure- relief effect of roof was obvious. Based on these,the parameters of roof pressure- relief roadway and pressure- relief area of large cross section chamber were desig ned. After pressure- relief roadway driven,directional throw blasting method was applied to the construction method of roof pressure- relief area.