This study developed a conceptual model for exploring the correlation between relational dimension of social capital and relation models in hope to reveal to what extent each elements in relational dimension of social capital influences the combination of relation models of knowledge sharing. Further we investigated the impact of each relation model on the effectiveness of knowledge sharing and attempt to present an efficient mechanism based on the combination of the four relation models. We adopted the survey method and focus on the members in IS project team to collect research data. Canonical correlation analysis was employed to examine the correlation between the two constructs, the relational dimension of social capital and the relation models of knowledge sharing, and two significant canonical functions with powerful explanation were derived. The first canonical function with major explanatory power showed that all the elements in the relational dimension of social capital are highly related with the models, CS, EM and MP, in the construct of relation models. The second canonical function, in which obligation is highly related with MP and AR, was derived with inferior explanatory power to the first one. Stepwise regression analysis was conducted to investigate the relationship between each relation model and the effectiveness of knowledge sharing. CS, among the four relation models, was found to have the highest positive significance with the effectiveness, followed by EM and MP sequentially, while AR was found no significant relation with the effectiveness of knowledge in our observations. With the results of this study, we hope to present an efficient mechanism for practitioners to promote knowledge management by enhancing corresponding social capital in relational dimension and offer comprehensive perspectives for researchers to achieve a better insight of the dynamics of knowledge sharing.