The quantum state number and free energy of the scalar field at the horizon of g eneral non-stationary black hole with charges are calculated and the result show s that the entropy of black hole is proportional to the event horizon area. This implies that the black hole entropy is just identical to the entropy of the qua ntum field on the event horizon. Taking into account the effect of the generaliz ed uncertainty principle on the black hole entropy and adopting the 2-D membrane model, the divergence in the brick-wall model is removed, without any cut-off， and the little mass approximations appear in the brick-wall model and the thin f ilm model are removed. Calculating the scalar field on the 2-D membrane outside horizon by using progression method we obtained some interesting results.