Food security constitutes a foundational cornerstone for social stability, with the achievement of sustainable agricultural production serving as a vital step towards this objective. Currently, the untimely harvesting of unripe wheat by farmers has led to a decline in food production, thereby posing a significant threat to the sustainability of China's food system and exacerbating food insecurity. Although the Chinese government has implemented various measures in response, their effectiveness has been limited. Limited scholarly literature exists on this particular issue. To advance food security in China, this study develops a tripartite evolutionary game model involving farmers, the government, and breeding enterprises. Adopting a systemic perspective, this study examines the interactions and impact mechanisms among these key actors during the wheat harvesting process. The findings indicate that the government should prioritize policies that enforce penalties. By implementing penalties within a reasonable range, the government can mitigate farmers' production costs and enhance the market price of grain. This approach discourages farmers from harvesting immature wheat and contributes to enhancing food security. Based on the research findings, this paper provides practical recommendations to guide the government in addressing food security governance issues.