The enthalpies of formation for polynitro compounds were predicted by using the molecular structure describers(MSD). With the different groups of polynitro compound molecules acting as descriptor codes (i.e. molecular subgraphs),multiple linear regression equation was established,of which the correlation coefficient is 0.9980. Most of the relative errors of the calculated values are within 10%. It can be seen that the calculated values of the enthalpies of formation are in good agreement with the experimental values.