It often appears some cognitive conflicts among the citizens¡¦ when evaluating the policy outcomes performance about Dengue fever prevention, since existed some characteristics in the input and outcome dimension, it include multi-involvers, multi-goals, multi-values and subjective judgement(Wang Ming-Shen and Chen Cheng-Liaou, 2004: 11). We taked the unfairness measurement approach of the Information Integration Theory (IIT) to explore the policy outcome performance about Dengue fever prevention. In this way, we constructed an algebraic model, namely ¡§Dengue Fever Basic Unfairness Measurement Model,¡¨ with accrute empirical test and validity criteria. According to the way of the factorial graph patterns and statistical interaction test of the model, we may analyze and collect these multiple information of policy outcomes(Farkas, 1991: 61 ; Anderson, 1996: 33). We obtained some important findings, include: 1.The citizen integrated the information of Dengue fever prevention outcomes by ¡¥averging¡¦ model, the experimental data support the mode and it had important policy implications. 2.The effort(implicit factor) of the governer¡¦s devoted to prevention tasks was more than the budget expendures(explicit factor) was the most important factor of outcome performance evaluation, and this had important cognitive implication. 3.According to the differences of the information qulity from the Dengue fever prevention, there was an interpersonal salience about the evaluation of the policy outcome performance. 4.It showed that highly corelation between the habitant¡¦s life modes and the prevention outcomes performance, this implied that the implicit social meaning of Dengue fever prevention were interpersonal interaction. 5.The citizen¡¦s perception of the unfairness measurement for the policy outcome performance of Dengue fever prevention were not satisfaction and sensitive to the interpersonal unfairness situation.