A distributed X-ray light source comprises: a plurality of arranged cathode assemblies used for emitting electron beams; an anode target used for receiving the electron beams emitted by the cathode assemblies; and compensation electrodes and focusing electrodes provided in sequence between the plurality of the cathode assemblies and the anode target, the compensation electrode being used for adjusting electric field strength at two ends of a grid structure in each cathode assembly, and the focusing electrode being used for focusing the electron beams emitted by the cathode assemblies, wherein the focusing electrode corresponding to at least one cathode assembly in the plurality of the cathode assemblies comprises a first electrode and a second electrode which are separately provided, and an electron beam channel is formed between the first electrode and the second electrode.