Contemporarily, the promotion and application of straw-to-field technology plays an important role in developing high-quality green agriculture, alleviating agricultural non-point source pollution and realizing the double carbon target. As the main subject of straw-to-field, a farmers’ willingness directly determines their straw-to-field behavior. To explore the influencing factors of farmers’ straw-to-field willingness and to improve the comprehensive utilization level of straw, this paper researches the relationship between government regulation, farmers’ subject cognition and straw-to-field willingness based on the survey data of 733 farmers in Heilongjiang province, and it examines the mediating role of farmers’ cognition in the process of government regulation affecting farmers’ willingness of straw-to-field. The results evidence that policy incentives and administrative constraints affect farmers’ willingness of straw-to-field by influencing ecological and technical cognition. However, farmers’ cognition of the cost and benefit of straw-to-field is biased; thus, this factor cannot effectively transform the willingness of straw-to-field into action.

As an important measure to promote the black soil protection strategy, returning straw to the fields is the choice of government policy to affect the decision-making behavior of farmers, and the policy implementation process is a dynamic game equilibrium process between farmers and the government. In order to explore the influence of policies on farmers’ straw-returning decision-making and stability processes, this paper used a logit model to analyze the influencing factors on farmers’ straw-returning decision-making behavior based on the survey data of 397 farmers in Hailun City, Heilongjiang Province. This study also constructs the evolutionary game model between farmers and government, carrying out a stability strategy analysis and numerical simulation. The results evidence that farmers’ cognition of fertilization technology, ecological protection, policy satisfaction and cognition of straw returning recipients have a significant negative influence on their willingness to return to the field, and the effect intensity decreases successively. What is more, cognition of crop disease resistance has a positive effect on the willingness of returning straw to the field. It is found that the game balancing process of farmers’ behavior and government straw returning policy evolution can be divided into three stages. At present, China’s straw returning policy is in the intermediate stage, and government needs to provide comprehensive compensation for returning straw to the field according to local conditions such as farmers’ willingness, crop conditions and so on.