A following and followed directed network was established based on Sina individual microblog.By analyzing social network centrality indicators applied to the microblog directed network, such as the node degree, closeness, betweenness and K-shell, the node centrality of the network was found.The results point out the important users and their roles in dissemination of information.Besides, the characteristics of the users on the microblog network were analyzed in order to reflect the personal interests and hobbies.The correlation between the social networks index and the degree of network was studied to reflect the relationship among the indicators.The results will help us to identify individual key nodes, and then analyze the information dissemination on individual microblog user network.