This paper introduces overconfidence to establish principal-agent model with multiple agents existing competitive relation under symmetric and asymmetric information situations．And analyzing the influence of overconfidence to agents and principal．The results show that：under asymmetric information situation，the agent’s overconfidence to the level of ability and the accuracy of information is positively correlated to his own effort level and his competitor’s effort level；the agent’s overconfidence to the level of ability is postively correlated to the decline rate of his effort level caused by asymmestric information and the cost of agent； the agent’s overconfidence to the accuracy of information is negatively correlated to the decline rate of his effort level caused by asymmestric information and the cost of agent．Which can provide some good advice to enterprises’s recruitment.