Abstract: The equation of status (EOS) should be used to predict power capability of explosives during the design of DNAN based melt-cast explosives to meet the requirements of warhead damage power. A method based on BKW program was used to predict JWL EOS parameters of explosives. The P-V curves of JWL EOS for typical explosives were achieved using the method. Comparisons of the calculated P-V curves with the cylinder test experimental P-V curves for typical explosives indicate that two curves agree very well at high and low pressure region, error less than 10% can be seen at medium pressure region. Acceleration process of copper plate was simulated with DNAN based melt-cast explosive JWL EOS parameters. The calculated velocity of central point in copper plate free surface agrees well with the experimental velocity of central point in copper plate free surface, the maximum error is less than 7%. Research results indicate that the method can be used to quickly predict the JWL EOS parameters and power capability of explosives during the period of designing DNAN based melt-cast explosive formulations.