Agroecological production strategies not only accomplish goals of food security (SDG #2- zero hunger) but also contribute to mitigating climate change (SGD #12 action for climate) through utilizing biological processes to reduce chemical dependence that creates hazards for the environment and human health. To provide an explicit picture of how agroecological rice cultivation can promote sustainable development through economic improvement and energy-saving, in-depth face-to-face surveys of 30 households who are applying organic rice farming and ecological practices in Chieng Yen communes, Son La, Vietnam were conducted between January and June of 2022. Comparative analysis of energy input-output balances and economic efficiency analysis between conventional and agroecological methods of rice production showed that the agroecological rice cultivation method can save up to 63% of energy inputs. The economic benefits of organic rice farming per hectare also rose 3 times compared to conventional paddy. Hence, agroecological rice farming in the study area is recommended to adopt and scale up among smallholders in the northern mountainous region of Vietnam as a successful example of climate-smart agriculture which ensures food security, adaption, and mitigation to climate change. A comprehensive approach is taken in the study to analyze energy use and efficiency as a tool of the circular economy at the sectoral or activity levels, something rare of studies in Vietnam.