In order to investigate the afterburning effects of aluminized explosives, the explosives of AⅨ-Ⅱand JAL were studied, and a double-layer test device filled with different gases and designed for enhancing the afterburning effects of under-oxidized explosives was used. The explosion energy outputs of the charges in the test device filled with oxygen, air, and nitrogen under different pressures were studied by underwater explosion test method. The shock wave energy, bubble energy and total energy were calculated respectively, and a method for calculating the energy of afterburning effect was introduced. The experimental results show that these experiments have excellent parallelism, the underwater explosion parameters are the same when they are at the same distance from the center of explosion, at the same depth and different directions, and the shock wave peak pressures accord with explosion similarity laws in the measuring range. This test device can enhance the afterburning effect of aluminized explosive significantly, in the studied range, the energy released by afterburning effect reaches the maximum value of 78% of the detonation heat. The underwater explosion method combined with the designed test device can measure the afterburning effect of aluminized explosives.