An FEL based energy driver for inertial confinement fusion (ICF) is proposed. Construction of such a driver becomes possible due to application of a novel FEL amplifier scheme — a multi-channel, multi-stage FEL amplifier with a diaphragm focusing line. The driving beam for the FEL amplifier is generated by the linear induction accelerator. The laser system operates at the radiation wavelength of 0.5 μm with the total energy of laser flash of 1.5 MJ, pulse duration of 4 ns and repetition rate of 40 pulses/s. Total efficiency (i.e. conversion efficiency of net electrical power to the radiation power) of the proposed system is equal to 12%. The brightness of the output radiation is 10 22 W/cm 2 sr. The scale and the cost of the FEL based energy driver are close to those of the heavy ion fusion driver.