Promoting green agricultural production is becoming increasingly important in order to address resource and environmental issues and meet consumers’ demand for safe agricultural products. Green agriculture mainly refers to the adoption of green, smart agriculture technologies in agricultural production. Farmers are the main body of agricultural production, so guiding farmers to adopt green, smart agriculture technologies is of great significance for safeguarding the ecological environment. However, due to the combined influence of internal and external factors, the current level of adoption of green, smart agriculture technologies by farmers is not high. Contract farming can have an impact on farmers’ production behavior through various channels, such as guiding and standardizing production, and may become an internal driving force for improving the adoption of green, smart agriculture technologies. How do farmers make contract farming selection decisions? How does the choice of contract farming affect farmers’ adoption of green, smart agriculture technologies? Further research on the above issues can provide useful references for promoting the development of green agriculture and ensuring the quality of agricultural products in China. Against this backdrop, this paper, using research data about rice farmers in the Jiangsu Province of China, adopted a gradual regression method for checking the mediating and moderating effects to discover the mechanism of how contract farming influences rice farmers’ choice of green, smart agriculture technologies. The research results showed that: (1) contract farming has an evidently positive influence on farmers’ choice of green, smart agriculture technologies; (2) the high ecological value standard plays a complete mediating role in the process of contract farming influencing farmers’ choice of green, smart agriculture technologies; and (3) the moderating effect of planting rice income exists and is significant. When the income from cultivation is high, the positive relationship between the high ecological value standard and farmers’ choice of green, smart agriculture technologies is strengthened. Income from rice cultivation does have a moderating effect. Therefore, the government can actively guide farmers to participate in contract farming by increasing its publicity and support of contract farming. The implementation of the high ecological value standard in contract farming should be refined. The government should complete the mechanism for selling quality agricultural products at good prices. Contract farming can make farmers and corporations involved have deep cooperation, increase the non-agricultural income of farmers, and further enhance the overall income of their households. Through these measures, the development of green agriculture can be achieved.