ObjectiveTo review the research progress and clinical application of allograft bone spacer in cervical and lumbar interbody fusion. MethodsLiterature about allograft bone spacer in cervical and lumbar degenerative disease was reviewed and analyzed, including the advantages and disadvantages of allograft material, fusion rate, effectiveness, and complications. ResultsFusion rate and effectiveness of allograft bone spacers were similar to those of autograft and polyetheretherketone spacers, and they were recommended by many orthopedists. However, indications, long-term effectiveness, and complications were not clear. ConclusionFurther study on allograft bone spacer in cervical and lumbar interbody fusion should be focused on optimal indications and long-term effectiveness.