A 100 J level of XeCl and KrF excimer lasers pumped by an intense relativstic electron beam (REB) accelarator Flash Ⅱ has been developed. The laser cell has an effective excitation volume of 24 liters and a 20×20 cm 2 aperture. The pump power density ranges between 1.5-2.0 MW/cm 3. The maximum output energy of 136 J with the pulsewidth of 50-100 ns and peak power of 1.5 GW is obtained for the XeCl (308 nm) laser. The divergence angle is 1.3 mrad by using the positive confocal unstable resonator technique. In KrF(248 nm) laser case, the maximum output energy is 157 J with pulsewidth of 80～100 ns and peak power of 2 GW.