The influence of compressive stress and Shore hardness on the annular gap defect of a casting polymer bonded explosive(P-1 explosive)charge after curing was studied using a compression technology. The relationship between stress and strain was analyzed. The equation of stress-strain for P-1 explosive compression curing process was obtained. The detection of the explosive was carried out by CT. Results show that the compressive stress is lower than 0.071 MPa and the compression modulus is 2.27 MPa when the strain is less than 3.232%. The values of stress and modulus rise rapidly when the strain is greater than 3.232%. The Shore hardness of the explosive increases from 3 HA to 59 HA after 5~25 h curing. When the initial value of Shore hardness is within 8~24 HA and the compressive stress of 14.2 kPa is imposed on the explosive, the compressive strain is 1.3%. The auxiliary compression technology can effectively eliminate the annular gap defect of the charge.