The invention provides a method for expanding a point mode discharge current range of a hollow cathode, relates to the technical field of expansion of the discharge current range of the hollow cathode and aims at solving the problem that the point mode discharge current range of the hollow cathode is narrow while the specific impulse of a whole propulsion system is reduced and overheating of the cathode is easily caused in a traditional method for expanding the point mode discharge current range of the hollow cathode. The method comprises the steps of (1) designing cathode parts according to the actual requirements of the hollow cathode and initially setting an internal migration distance of a throttling hole; (2) enabling the cathode to normally work and measuring working parameters of the hollow cathode; (3) optimizing the internal migration distance of the throttling hole according to the working parameters of the hollow cathode, enabling the cathode to normally work and measuring the working parameters of the hollow cathode; and (4) repeating the step (3) until the optimized internal migration distance of the throttling hole is found out. The method is suitable for expanding the point mode discharge current range of the hollow cathode.