The continuous specific heat capacities at constant pressure (C_p) of energetic materials of mono-substituted potassium (K₁TNPG), di-substituted (K₂TNPG) and tri-substituted (K₃TNPG) trinitrophloroglucinate were measured by differential scanning calorimeter (DSC) method. The change of enthalpy and entropy were calculated at an interval of 5 ℃ in the range of 50-100 ℃. The least square method is applied to treat experimental data. The temperature dependence of C_p was determined as quadratic equation: C_p=a+bT+cT². The correlation coefficients (R) of measured results of K₁TNPG, K₂TNPG and K₃TNPG are 0.987, 0.999 and 0.993, respectively. The deviation analysis indicates that DSC method is effective and can be used to measure the specific heat capacity of other energetic materials.