Abstract: The progress of research on the effect of active ingredients of Astragalus membranaceus on regulation of immune balance of helper T cell 17/regulatory T cell (Th17/Treg) was reviewed in the article. As a traditional herbal medicine, Astragalus membranaceus has a wide range of pharmacological activities and clinical application value. The active ingredients Astragalus polysaccharides and Astragaloside have remarkable effect on immune regulation, inhibit the differentiation and function of Th17 cell, and increase the number and function of the Treg cell. They affect the immune balance of Th17/Treg cell, inhibit the pathological process of excessive immune stress of autoimmune disease, allergic disease and infectious disease, and alleviate the inflammatory response by regulating signaling pathways of immune cells, inhibiting the emergence of anti-inflammatory factors and regulating immune tolerance. Therefore, Astragalus membranaceus and its preparations as well as active ingredients hold the potential for alternative drugs for treatment of infectious inflammatory diseases, allergic diseases, inflammatory bowel diseases and autoimmune diseases. It is necessary to further explore the action mechanisms of the active ingredients of Astragalus membranaceus and safety and effectiveness in clinical application so as to provide theoretical bases for expansion of Chinese patent preparations such as Astragalus injection and Astragalus granules and clinical promotion.