The study applied for a social network analysis tool and HLM method to analysis cross level dataset which will specify an integrated ¡¥meso¡¦ framework of linking diversified relationships and employees¡¦ attitudes and behavior within the work group settings. The effective sample size of this study collected by whole completed survey involved 317 employees within 26 different workgroups representing diversified industries in Taiwan. This study provided evidence that density of informal development network (informal network, advice network, and mentoring network) are related to both employees¡¦ intention to stay and individual job performance. As hypothesized, both In-degree centrality of advice network was positively related to individual job performance. Perceived career success was positively related to in-degree centrality of advice network. In-degree centrality of friendship network was negatively related to intention to stay. Furthermore, Density of mentoring network will be positively related to intention to stay and individual job performance. Density of advice network was related negatively to individual job performance and density of friendship was related positively to individual job performance. The effect of in-degree centrality of advice network on individual job performance will be partially mediated by mediating variable - perceived career success as well as the effect of in-degree centrality of friendship network will be partially mediated by mediating variable - perceived career success.