To reveal the relationship between physiological indices in apples and resistance to woolly apple aphid (Eriosoma lanigerum Hausmann), and provide basis for breeding resistant cultivars. Apple cultivars with different resistibility were selected through field survey, the physiological indexes and the changes of them damaged by E. lanigerum in the apple cultivars were studied. Result: In the uninjured branches, the contents of soluble sugar (r=0.99) and protein (r=0.86) are positive correlated with the hazard ratios of woolly apple aphid; amino acid contents are negative corrected with the hazard ratios(r=-0.96); total phenolic compound and enzyme activities have no significant relationship with the resistance to E. lanigerum. After been infested the sugar contents in Fuji and Golden Delicious increased by 1.4% and 7.0%; protein contents, amino acid contents and total phenolic compound contents decreased in all cultivars, the rates of change in total phenolic compound have obvious relationship with the hazard ratios(r=0.94) and the phenolic compound decreased by 23.5% in Red Fuji; the SOD (Superoxide Dismutase), CAT (Catalase) activities were increased in all the injured cultivars, the rates of increase in CAT are positive correlated with the hazard ratios(r=-0.92), and increased by 91.2% in Zhaojin108; PPO (Polyphenol Oxidase) and POD (Peroxidase) activities have no regularly changes; in Golden Delicious all the four enzymes were increased. It is suggested that the resistant cultivar has high amino acid contents and low soluble sugar, protein contents. In the injured branches of resistant cultivar the amino acid were decreased obviously and the phenolic compound, soluble sugar were decreased slightly. Enzyme activities have no significant relationship with the resistance to E. lanigerum.