Nowadays the natural science theory has been widely used, especially in the field of complex social systems, which attracted great attention. The opinion means the individual's preferences or views under one topic. Most research on opinion dynamics have focused on the evolution process of how opinion reach a convergence, from disorder to order. Based on flocking theory and the study of agent, we proposed a model of individual opinion evolution. The emergence of cluster and how the opinion evolve has also been studied in our paper. The simulation analysis provide a good explanation for the realistic phenomena.