Abstract: Objective To study the effects of lute in,daidzein,and lecith in on cognitive behavior in mice.Methods The lute in,diadzein,lectith in and their combina tions were admin istered to male Kunming mice with gavave for six weeks.Then stepdown test and Morris water maze test were conducted.The biochemical indices for serum and braintissue of the mice were measured.Results The contents of malondialdehyde in the brain of diadzein group(3.4±0.4 nmol/mg#prot),lecith in group(3.4±0.4 nmol/mg·prot),and combination group(3.2±0.3 nmol/mg·prot)were significantly lower than that of blank control group(3.8±0.5 nmol/mg·prot,P<0.05 or P<0.01).The latency periods of Morris water maze test for lute in group(23.09±6.59s),daidze in group(22.29±7.33s),and combination group(21.45±5.45s) were significantly lower than that of the control group(45.80±9.70s,P<0.05 or P<0.01).The contents of 5-hydroxy tryp tamine in the brain of lutein group(210.08±20.46 ng/ml),daidze in group(222.95±15.87 ng/ml),lecith in group(225.18±24.56 ng/ml),and combination group(237.97±29.30 ng/ml)were significantly higher than that of the control group(171.61±32.94 ng/ml,P<0.01 for all).The contents of norepinephrine in the bra in of lute in group(101.22±6.29 ng/ml),lec ithin group(106.12±7.25 ng/ml),and combination group(108.84±16.94 ng/ml) were significantly higher than that of the control group(93.25±7.33 ng/ml,P<0.01 or P<0.05).Conclusion The cognitive behavior could beame liorated in different extent by oral administration of lute in,daidzein,lecithin lonely or combined in mice.