In the context of guaranteeing national food security and promoting the development of new agricultural operating entities，it is of great theoretical and practical significance to identify intrinsic motivational factors that can effectively encourage these entities to engage in farmland quality protection.Based on the Motivation-Opportunity-Ability（MOA） theory，this paper constructs a theoretical model to examine how the entrepreneurship of large-scale grain farmers affect their farmland quality protection behavior.Utilizing a sample of 517 households obtained from field surveys in the major grain-producing provinces （Hubei，Hunan，Henan，Jiangxi，Jiangsu，and Anhui），we systematically analyze the effect of farmers’ entrepreneurship on their decisions regarding farmland quality protection by controlling for economic and non-economic factors affecting farmland quality protection behavior.The results show that entrepreneurship among large-scale farmers positively influences their farmland quality protection behavior.Moreover，both social network and entrepreneurial ability positively moderate the relationship between entrepreneurship of large-scale farmers and their farmland quality protection behavior.Additionally，the institutional completeness at the grassroots institutional completeness at the moderating effect of entrepreneurial ability.Specifically，when local institutions are more developed，entrepreneurial ability strengthens the positive relationship between entrepreneurship and farmland quality protection efforts.The study concludes that guiding and strengthening entrepreneurship among large-scale farmers represents a valuable approach to promoting farmland quality protection，complementing policy-based and economic incentives.Based on the results，targeted recommendations are proposed.