Abstract: Due to the mix and uncertainty of the microblog information data, the credibility assessment has difficulty to distinguish. An argumentation directedgraphical model for microblog credibility assessment is presented. From the point of view of argumentation, the model, the argument deduction process is described intuitively by graphical model. In the credibility assessment process, we create the argument node based on the relevant topic corpus, define the rule credibility by the thematic sentiment and potential logical relationship, set the weights on the edges, and represent the defense and attack strength between arguments for this reason. The conclusion credibility is achieved and the argumentation graphical with recursion is evolved according to the relevant algorithm. At last the distinguish information could get the credibility. Experimental results show that this model obtains an accuracy up to 6% in comprehensive indexmeasure compared to the traditional methods.