In an inertial fusion energy (IFE) reactor of 1000-MW(electric) fusion power, 95% flibe and 5% fuel with DRc thickness instead of 100% flibe are used At startup, the tritium breeding ratio and M-blanket energy multiplication ratio are 1.05 and 1.26 for UF4 and DRc approximate to 60 cm, respectively. These values increase during an operation period of 30 yr. In 11 yr, M increases from 1.26 to 2 [= 2000 MW(electric)]. After operation of 11 yr, the energy production is stabilized by means of separation of produced plutonium. After 30 yr, displacement per atom (dpa) and helium production in the first wall are calculated as 92 dpa and 590 ppm, respectively. In addition, the cost of electricity values of the HYLIFE-II and the improved HYLIFE-II of 2000 MW(electric) drop from 4.5 and 3.2 c/kW(.)h to 4.18 and 3.00 c/kW(.)h, respectively. On the other hand, the IFE reactor has the fissile fuel breeding potential of 70 tonnes. The fissile fuel of 45 tonnes corresponding to approximate to2350 kg/yr would be sufficient to provide makeup fuel for approximate to10 light water reactors after 11 yr. After the shutdown process, 25 tonnes of fissile fuel with fuel enrichment of 23% would be left over.