The promotion of agroecological technology is of great significance in transforming agricultural development mode and promoting the agricultural modernization. Taking rice-crayfish co-culturetechnology as an example, this study empirically analyses the impact of expected return and technology subsidy on farmers’ adoption of agroecological by using microscopic survey data of 935 farmers in Hubei, Hunan and Anhui provinces in the middle and lower reaches of the Yangtze River. The results show that the expected return and technology subsidy both have a significant positive effect on Farmers’ adoption of agroecological technology. Moreover, there is an interactive effect between expected return and technology subsidys on farmers’ adoption of agroecological technology. Given the same technology subsidy, the higher expected return of farmers, the more it contributes to agroecological technology adoption behaviour. In terms of the quantity of human capital, there is significant heterogeneity in the effect of expected return and technology subsidy on farmers’ adoption behavior of agroecological technology. In addition, there are significant intergenerational differences in the impact of expected return on farmers’ adoption of agroecological technology. Adoption behaviour of older generations of farmers is generally influenced by expected returns, while intergenerational differences do not show significant intergenerational differences in farmers’ adoption behaviour of agroecological technologies.. Therefore, the government should strengthen the top-level design and formulate a systematic subsidy scheme for rice-crayfish co-culture technology, so as to better play its promoting role. In the meantime, it is proposed to enhance farmers’ expectations of the return of rice-crayfish co-culture technology, increasing their motivation to adopt it, and thus achieve sustainable development of the rice-crayfish co-culture technology.