With Chinese yams (Jiaozuo， Henan) and normal yams (Zhoukou， Henan) as the research object， different cooking methods (steaming or boiling) are performed to investigate the effects on the edible quality， in vitro digestibility and predicted glycemic index (preGI) of different parts of yam rhizome and different retrogradation time. The results show that the different cooking methods had obvious impact on the hardness， viscosity， elasticity， chewability， L*， a*， b* of Chinese yams / normal yams. Under the same cooking method， different retrogradation time had little effect on the quality of different parts of Chinese yams， but had a great effect on the quality of different parts of normal yams. From the perspective of sensory analysis， the sensory score of Chinese yams was higher than that of normal yams under same cooking method， and the sensory score was the highest for two yams under hot water steaming and retrogradation for 1 h. The preGI value of unprocessed Chinese yam was significantly lower than that of unprocessed normal yam. Besides， the preGI value of Chinese yams was lower than that of normal yams under hot water steaming. Under the best sensory evaluation condition of steaming in hot water， the content of RS and RS+SDS of Chinese yams was higher than that of normal yams. The study can be expected to establish the relationship between the main cooking method and the food edible quality， which could guide consumers to choose appropriate cooking method with different preferences.