To solve the cracks in the pressing process of RDX-based PBX(polymer bonded explosive), the influence of pressing temperature, cooling rate and heating rate on quality of Φ60 mm×60 mm RDX-based PBX were studied with ultrasonic, X-ray, and density detection. Results show that the number of cracks in the PBX diminish or eliminate when the cooling temperature is higher than 45 ℃, and the cooling and heating rates are less than 5 ℃·h^-1 in compaction process. Moreover, increasing pressing temperature improves the machining and pressing quality of the PBX.