This paper was to investigate the effects of life satisfaction expectancy, mindfulness and social support of marital middle-aged women on depression. This survey was conducted from March, 2009 to June, 2009 and 182 responses from the survey were used for the analysis. The data was analyzed by descriptive statistics, t-test, ANOVA, psarson correlation and Multiple Regression. The research findings could be summarized as the followings. First, the mean score of life satisfaction expectancy, mindfulness, social support of the marital middle-aged women were higher, while, the mean score of depression are lower relatively. Second, among the main factors, life satisfaction expectancy, social support were the significant predictor to explain depression of marital middle-aged women. Third, the depression of marital middle-aged women was not significantly influenced by mindfulness.