The essence of Chinese medicine diagnostics is the treatment based on syndrome differentiation.However，syndrome differentiation of Chinese medicine is based on four diagnostic methods as inspection，auscultation，interrogation and palpation to integrate all kinds of clinical information and make accurate diagnosis on disease.The authors collected researches on objectification of the four diagnostic methods of Chinese medicine for diabetes mellitus in recent ten years，systematically summarized and concluded the research progress of Chinese medicine scholars on objectification of etiology and pathogenesis， tongue manifestation， pulse manifestation，face diagnosis， auscultation?and?nterrogation at present，and offered an outlook of the future trend of the objectification of diabetes mellitus.