Abstract. -We propose a consensus opinion model based on the evolutionary game. In our model, both of the two connected agents receive a benefit if they have the same opinion, otherwise they both pay a cost. Agents update their opinions by comparing payo?s with neighbors. The opinion of an agent with higher payoff is more likely to be imitated. We apply this model in scalefree networks with tunable degree distribution. Interestingly, we find that there exists an optimal ratio of cost to benefit, leading to the shortest consensus time. Qualitative analysis is obtained by examining the evolution of the opinion clusters. Moreover, we find that the consensus time decreases as the average degree of the network increases, but increases with the noise introduced to permit irrational choices. The dependence of the consensus time on the network size is found to be a power-law form. For small or larger ratio of cost to benefit, the consensus time decreases as the degree exponent increases. However, for moderate ratio of cost to benefit, the consensus time increases with the degree exponent. Our results may provide new insights into opinion dynamics driven by the evolutionary game theory.Introduction. -The dynamics of opinion sharing and competing and the emergence of consensus have become an active topic of recent research in statistical and nonlinear physics [1]. One of the most successful methodologies used in opinion dynamics is agent-based modeling. The idea is to construct the computational devices (known as agents with some properties) and then simulate them in parallel to model the real phenomena. In physics this technique can be traced back to Monte Carlo simulations. A number of agent-based models have been proposed, which include the voter model [2], the majority rule-model [3,4], the bounded-confidence model [5] and the social impact model [6]. Some models display a disorderorder transition [7][8][9][10][11][12], from a regime in which opinions are arbitrarily diverse to one in which most individuals hold the same opinion. Other models focus the emergence of a global consensus [13][14][15][16][17][18], in which all agents finally share the same opinion.In this Letter, we propose an opinion model based on the evolutionary game. Evolutionary game theory as a powerful mathematical framework, has been widely used to understand cooperative behavior [19,20], traffic flow [21,22], epidemic spreading [23,24] and so on. However, to the best of our knowledge, the impact of evolutionary games on the