Objective: To establish a bidirectional fermentation system of Paecilomyces cicadae/Astragalus membranaceus and Astragalus membranaceus residue,and to explore the content change of active ingredients in fermentation process. Methods: The inoculation amount,temperature and humidity were optimized by orthogonal design method,and the contents of polysaccharide,total flavonoids and total saponins were determined by sulfuric acid-phenol colorimetry,NaNO_2-Al(NO_3)_3 colorimetry and vanillin-perchloric acid oxida...