In order to explore the effect of 3，4-dinitrofurazan （DNTF） on the explosive energy release process of layered composite thermobaric charges， various double-layer composite charges were prepared， with the content of aluminum powder in the outer charge adjusted from 60% to 94%， and the content of DNTF adjusted from 40% to 0. Then， explosion tests were carried out in a closed tank under nitrogen and air environment. Based on the correlation between quasi-static pressure and effective mechanical energy， the released energy of charges at different reaction stages was obtained. Moreover， the afterburning process of aluminum powder from different charges was analyzed according to the evolution of fireball. The results reveal that the dispersed DNTF particles are easy to be ignited and grow rapidly after being shock-dispersed when the mass fractions of DNTF in the outer charge is 40%， which can improve the anaerobic combustion rate of aluminum powder and the aerobic combustion rate of aluminum powder at the edge of the cloud， thus the combined mechanical energy released during detonation and anaerobic combustion is raised 12% than that of the homogeneous charge with same composition. Whereas， when the DNTF in the outer charge is replaced by polytetrafluoroethylene （PTFE） in the same proportion， the combustion rate after dispersal is significantly reduced as well as shock wave overpressure and temperature， and the total mechanical energy released decreased by about 22% than composite charge containing DNTF in its outer layer. Moreover， when the outer charge is all replaced by aluminum powder， intensely aerobic combustion with longer duration will occur in the high-concentration aluminum powder cloud， the total mechanical energy released drops by only 5%， while the combined mechanical energy released by detonation and anaerobic combustion drops by 32%， and the peak shock wave overpressure has a considerable reduction. The above indicates that DNTF in the outer layer of the composite charge plays an important role in enhancing the combustion rate of the aluminum powder cloud and energy release rate in the early explosion stage.