Even though both empirical studies and field evidences show that Bt cotton can significantly reduce pesticide use, Chinese farmers are still spraying excessive pesticide in field production. Based on primary household surveys in the North China Plain, this study shows that farmers' lack of knowledge on pest management and pesticide use is strongly correlated with their excessive pesticide use. According to this study, improving farmers' awareness and knowledge could potentially reduce pesticide use by 10–15%. The paper concludes with policy implications.