Depressive symptoms are important risk factors for developing major depression. Thus, to explore early detection and its’ mechanism of depressive symptoms of the elderly is very important. Cognitive bias may play an important role in the onset and maintenance of depression. Interpretative bias is a kind of usual cognitive biases, and the type of interpretative bias is associated with such dysfunction that involves the preferential interpretation of an ambiguous stimulus, context and event as possessing a meaning that is consistent with his/her concerns. The present studies investigated the relationship between depressive symptoms and interpretative bias of the elderly through the questionnaire, behavioral experiment and ERP experiment. On this basis, the auxiliary tool for the detection of elder’s depressive symptoms at early stage has been developed. Results show that: 1. Center for Epidemiological Studies Depression Scale (CES-D) was used to 3768 participants whose ages were 60 years or older in a national sample, the prevalence of depressive symptoms is 40.6%. The levels of depressive symptoms of elder with spouse alive were significantly smaller than ones of elder with other marital status. White-collar worker were significantly smaller than the manual worker in the level of depressive symptoms. The more educational levels they were, their depressive symptoms smaller. Gender differences in depressive symptoms were not significant, but the interaction with gender and age was significant, within the 71-80 years group, the depressive symptoms of female higher than male. Depressive symptoms of 60-65 years of age group were lower than 76 years or over group.