Provided are an on-chip miniature X-ray source and a method for manufacturing the same. The on-chip miniature X-ray source includes: an on-chip miniature electron source; a first insulating spacer provided on an electron-emitting side of the on-chip miniature electron source, where the first insulating spacer has a cavity structure; and an anode provided on the first insulating spacer, where a closed vacuum cavity is formed between the on-chip miniature electron source and the anode. The on-chip miniature X-ray source has the advantages of stable X-ray dose, low working requirements for vacuum, fast switch response, capability of integration and batch fabrication, and can be used in various types of small and portable X-ray detection, analysis and treatment devices.