The problem of measuring conflict in large-group decision making is examined with every decision preference expressed by multiple interval intuitionistic trapezoidal fuzzy numbers(IITFNs).First,a distance measurement between two IITFNs is given and a function of conflict between two members of the large group is proposed.Second,members of the large group are clustered.A measurement model of group conflict,which is applied to aggregating large-group preferences,is then proposed by employing the conflict measure of clusters.Finally,a simulation example is presented to validate the models.These models can deal with the preference analysis and coordination of a large-group decision, and are thus applicable to emergency group decision making. The problem of measuring conflict in large-group decision making is examined with every decision preference expressed by multiple interval intuitionistic trapezoidal fuzzy numbers (IITFNs). First, a distance measurement between two IITFNs is given and a function of conflict between two members of the large group is proposed. Second, members of the large group are clustered. A measurement model of group conflict, which is applied to employing large quantities of group preferences, is then proposed by employing the conflict measure of clusters. Finally, a simulation example is presented to validate the models. These models can deal with the preference analysis and coordination of a large-group decision, and are therefore to emergency group decision making.