Abstract: A 1Hz repetitionrate electron beam generator is being developed to pump HF/DF chemical laser. The pulse width, peak current and peak voltage of the electron beams are 100ns, 100kA and 450kV, respectively. It uses two diodes, two waterfilled pulse forming lines, three lasertriggered switches, a pulse transformer and one set of energy storage capacitors. The primary, secondary and mutual inductances of the pulse transformer are 331nH, 26.5mH and 1.9μＨ, respectively. The capacitance of each pulse forming line is 8.15nF. Its inductance and impedance are 300nH and 6.2Ω, respectively. The breaking factor is 03 at 1MV charging voltage. The output energy of a nonchain HF/DF chemical laser pulse is expected to be 250J at 38μm.