Abstract: The discharge characteristics of hollow-cathode of ion thruster,in the ignition,steady-state operation and extinguishing stages,were theoretically analyzed and experimentally evaluated with the lab-built test platform.The influence of the commercial power-supply on the typical volt-ampere characteristics was investigated with dynamic balance equation and via orthogonal design.The results show that when it comes to hollow-cathode driven by commercial power-supply,the hollow-cathode was stabilized at the 2^nd operation point(Q) with lower impedance after passing the 1^st operation point(A) in ignition to steady-state transition; the steady-state V-I curve exhibited a typical negative impedance characteristics; and the increases of emission current and xenon flow-rate improved the emission efficiency.The lowest input-power to maintain steady-state discharge of LHC-5 L ruthenium hexaboride cathode was 14 W,below which the hollow-cathode discharge will be extinguished.