Two general expressions and their six derived formulae for estimating the critical temperature (T_b) of thermal explosion for energetic materials (EMs) are derived from the Semenov′s thermal explosion theory and eight non-isothermal kinetic equations, using reasonable hypothesis. The initial temperature (T_0i) at which DSC curve deviates from the baseline，the onset temperature (T_ei), the kinetic parameters of exothermic decomposition reaction can be obtained from the non-isothermal DSC curve of EMs. The values of T₀₀ and T_e0 was obtained from the equation T_{0i or ei} = T_{00 or e0} + a₁ β_i + a₂ β_i² +…+a_L-2β_i^L-2,i=1,2,…, L and then the values of T_b was calculated by the six derived formulae. The T_b results obtained with the six derived formulae for 1, 4, 5, 8-tertanitro-1,4,5,8-tetraazadifurazano［3,4-c:3′,4′-h］ decalin and its parent compound, 1,3,4-trinitro-imidazolonone［4,5-b］ furazano［3,4-e］ piperazine and its parent compound, 1,3,4,8-tetranitro-imidazolinone［4,5-b］ furazano［3,4-e］ piperazine, 1,4,5,8- tetranitro -1,4,5,8-tetrazafurazano［3,4-b］ decalin and 1,3,5-trinitro-1,3,5-triazafurazano［3,4-f］ cycloheptane approximate well to each other.