The integration of agriculture and tourism heavily depends on agricultural resources, and in turn, it can also contribute to agricultural sustainability. Based on panel data from 30 provinces in China from 2008 to 2019, the relationship between agriculture and tourism integration and sustainable agricultural development is empirically analysed using the fixed effect model, system GMM model and spatial Durbin model. Results are as following: (1) The level of sustainable agricultural development (SADL) and the level of integration of agriculture and tourism (ATL) increase steadily during the study period, presenting obvious spatial agglomeration characteristics. (2) ATL has a positive impact on SADL. So improving the integration of agriculture and tourism can contribute to promoting sustainable agricultural development. (3) SADL of the previous period has a significant influence on the level of SADL of the current period, showing strong path dependence and inertia effects. Even so, the integration of agriculture and tourism is still effective in promoting the sustainable development of agriculture. (4) The effect of ATL on SADL has a spatial spillover effect. That is, the integration of agriculture and tourism in a region can promote sustainable development of agriculture in its neighbouring provinces. Based on the above findings, this paper proposes policy recommendations for the integral development of agriculture and tourism and promotion of the sustainable development of agriculture.