Abstract: The classical time discrete scheme does not consider the self adaptive time step and the physical quantity about differential quantity for time variable exits numerical oscillation.Therefore,the numerical precision is very poor.In this paper the time discrete scheme is studied for the spherical time-dependent neutron transport equation.The modified time discrete scheme is constructed for self adaptive time step.The numerical results show that the modified time discrete scheme is very simple and has more accurate numerical precision.The iteration number for modified time discrete scheme is lower than that of the conventional exponential method and diamond difference.Furthermore,the differential curve on time about flux is more smooth than that of the exponential method and diamond difference.