Abstract Heretofore a substantial amount of researches involve gratitude and life satisfaction. It has been demonstrated that gratitude is a unique predictor of life satisfaction, and the relation between them may be causal. The mediators which may impact on this causality were also well-studied separately, while few researchers were concerned with the possible correlation between them. Moreover, in view of the personality which is correlated with these variables, it is necessary to filtrate feasible mediators and to seek out the special mechanism of gratitude to the life satisfaction, via controlling the influence of the personality. Thus, the purpose of this study is to explore which of the selected 4 mediators- affect, self-esteem, self-efficacy and coping style- bring definitely significant effect on the predictive role of gratitude, even the causal relationship. The current study hypothesized that: (1) the effect of affect, self-esteem, self-efficacy and coping style on life satisfaction may be influenced by personality; (2) one of the 4 mediators may be the major explanatory variable of gratitude’s unique predictive status. 338 college students were recruited and investigated through seven related questionnaires in this survey: the Gratitude Questionnaire Six(Revised), the Satisfaction with Life Scale, the Positive and Negative Schedule(PANAS), the Self-esteem Scale, the General Self-efficacy scale, the Neuroticism Extraversion Openness Five-Factor Inventory(NEO-FFI-R) and the Simplified coping style questionnaire(SCSQ) were respectively used to assess gratitude, life satisfaction, positive & negative affect, self-esteem, general self-efficacy, personality and the coping style. Except the independent variable, the dependent variable and the personality variable, the rest were the feasible mediators. A couple of software, SPSS and Process, were applied in the research. All the variables were calculated into the total score. The Pearson correlation was used to analysis the collected data; hierarchical regression was used to exclude the overlapped effect of the mediators under the control of personality, and to reject the influence of personality among the left mediators; Process programmed by Hayes were adopted to test the mediating effect of self-esteem and positive affect between gratitude and life satisfaction, after controlling the influence of personality and gender. The main results revealed that: (1) gratitude significantly correlated with life satisfaction and the mediators, and the chosen mediators were associated with each other, which can be seen clearly in Table 1; (2) the main effect of gratitude was significant after controlling the impact of gender and personality; (3) the general self-efficacy、coping style and negative affect was excluded because of the insignificant coefficient of regression to the life satisfaction, which can be seen in Table 3; (4) of all the mediators, only the mediating effect of self-esteem was significant via controlling personality and gender. The process was showed in Table 4. Accordingly, we conclude that in the four selected mediators it is the self-esteem that partially mediates the causality of gratitude and life satisfaction. Meanwhile, the relation between self-esteem and life satisfaction may be causal for the controlling of the possible variables. That is to say, self-esteem may be the antecedent of life satisfaction. Moreover, when personality is controlled, the coping style, negative emotion and general efficacy bring insignificant effects on life satisfaction, showing the co-variation with personality on the effect of life satisfaction. Self-esteem, positive emotion still works after controlling personality and gender, and there may be some complicated mediating relations, which may conduce to complete the path in “gratitude - life satisfaction” model, deserving further exploration. The present study clarifies possible mediators in the research of gratitude and life satisfaction, averting pointless exercises in further investigation. Meanwhile, further research is necessary to explore the relationship between self-esteem and life satisfaction.