Fine-grained Fe-Al energetic materials have high reaction enthalpies, and the release energy of the iron phase and a large portion of the active aluminium phase in sintered materials enables the replacement of conventional materials in new types of weapons. To study the energy release characteristics of fine-grained Fe-Al energetic jets under impact loading, a dynamic energy acquisition system is established to quantify the energy generated by the response of fine-grained Fe-Al energetic jets to impact targets. The pressure-time curves of fine-grained Fe-Al energetic jets with different ratios under different impact conditions are obtained, and a method for calculating the pressure differential value is proposed to quantitatively determine the energy release values of fine-grained Fe-Al energetic jets. The energy release mechanism of the Fe-Al energetic jet is analysed at the micro-level by recovering the reaction products. The results show that there is an optimal Fe-Al ratio that attains the greatest energy release effect from fine-grained Fe-Al energetic jets. With increasing impact energy, the energy released by energetic jets tends to increase, and an impact energy threshold that saturates the chemical reaction of energetic materials in the jets exists. The relationship between the impact conditions and the energy release value of fine-grained Fe-Al energetic jets is established.