Abstract: The adaption modifications of MCORGS, which is a couple package for 3D neutron transport code MCNP and burnup code ORIGENS, were made in order to analyze and improve the laser inertial confinement fusion-fission energy (LIFE) proposed by Lawrence Livermore National Laboratory. In the new package, a tritium control module and a thermal power control module were added. An equivalent neutronics model, which used depleted uranium as fuel and Be as neutron multiplier, was designed according to relative researches about LIFE. The numerical simulations validated the MCORGS code. For the lack of Be resources and the complexity in cooling Be multiplier, a new blanket design which used depleted uranium as fuel and Pb as the neutron multiplier was proposed. The energy multiplication in the new blanket is 4 and the power of 2000 MWt can be maintained during 55 a.