Abstract: In the report， the blow-up problem of the solution of nonlinear reaction diffusion equation in finite time was studied， in which the model simulates some combustion processes. If the solutions satisfy the nonlinear conditions at the boundary of the region， the auxiliary functions are constructed， and the energy estimation method and the differential inequality technique are used to prove the blasting result in a finite time， and the upper bound of the blasting time is obtained. Under some special limiting conditions， the existence of global solutions was proved.