The design and production methods of two large electromagnetic pulse simulators at system level are explained. As bounded-wave electromagnetic pulse simulators, each of them is made up of a flat plate transmission line, a pulsed power source and a matched load. By taking several measurements, the bounded-wave electromagnetic pulse simulator generates a vertically polarized electric field with a rise time of 2.7 ns and a full width at half maximum of 25.6 ns. The working volume is 8.4 m×8.4 m×8.4 m and the maximum electric field amplitude is 50 kV/m. The second electromagnetic pulse simulator is a radiating wave electromagnetic pulse simulator, which is made up of an antenna and a pulsed power source. The radiating-wave electromagnetic pulse simulator generates a horizontally polarized electric field with a rise time of 10 ns and a full width at half maximum of 30 ns. The maximum electric field amplitude is 15 kV/m with the reference sensor at 20 m below the source.