Abstract: In order to reveal the mechanism of the increase of solidification and cooling rate of melt-casting explosive by increasing the pressure of the casting vessel, the interfacial heat transfer coefficient (IHTC) between the explosive charge and the mold was determined by the one-dimensional thermal conductivity experiment and the numerical inversion method, which was a function of both the time for solidification and cooling and the pressure of the casting vessel. The results show that the IHTC is increasing with the increase of the applied pressure, which is responsible for increasing the solidification and cooling rate of the explosive charges.