The effects of different processing methods (peeling， with skin， extrusion， fermentation and frying) on the contents of total phenols， total sugars， total flavonoids， isoflavones， alkaloids and antioxidant activities (DPPH， ABTS+ scavenging and FRAP system)， α-glucosidase inhibition of Apios americana Medik were evaluated by simulated digestion in vitro. Compared with the processing control group， the contents of total phenols， isoflavones and alkaloids increased by 73.46%， 42.02% and 56.61% respectively in the fermentation treatment， 19.68% in the extrusion treatment and 31.19% in the frying treatment. The antioxidant capacity of DPPH， ABTS+ and FRAP increased by 6.81%-19.77%， 21.02%-41.96% and 3.24%-35.99%， respectively； At the same time， the effect of simultaneous fermentation on α-glucosidase inhibition rate increased by 33.6%. Among the five processing methods， fermentation is the best method to retain the total phenols， isoflavones and alkaloids， extrusion is the best method to retain the total flavonoids， and frying is the best method to retain the total sugar.