Abstract: In a “company + farmer” mode of agriculture, the participation of leading companies, the degree of effort of farmers and the production capacity influence the success of this mode. If companies participate in agricultural tasks, whether farmers will try their best to fulfill their tasks and how companies design incentives to encourage farmers to complete agricultural tasks better and create higher output value are studied. Under the condition of information asymmetry, the principal-agent model between companies and farmers is established to study the impact of the company's participation in investment behavior and farmers' output value capacity on the incentive intensity, effort and income. The research shows that the involvement of the company can promote the efforts of farmers and the incentive coefficient will increase, but when it reaches a certain level, the growth rate will slow down. The output value of farmers will stimulate the enthusiasm of their work and they can achieve higher reward; if the ability of farmers' output value is high, it's more likely to attract the company's involvement. If companies actively participate in agricultural tasks, income will increase; the other hand, the companies' earnings are decreased. Finally, the relevant conclusions are verified by a numerical simulation.

Key words: company+farmer, participate in input, production capacity, incentives