A rapid development in regional economy is often accompanied by an increase in energy consumption and the intensification of environmental pollution, which brings great pressure to the social economy and the natural environment. In order to solve the integrated problem of economic, social, and natural factors, we propose an evaluation method for the sustainable development of the regional economy, based on emergy. By analyzing the statistical data of Henan’s economic development from 2010 to 2018, an evaluation index system of regional eco-economic sustainable development was constructed based on four aspects: natural subsystem, economic subsystem, social subsystem, and sustainable development index. The index system was then used to measure and comprehensively evaluate the sustainable development of the ecological economy and the environmental friendliness of Henan Province. The assessment results showed that the emergy self-sufficiency rate decreased, indicating decreased self-sufficiency. Moreover, the environmental load rate was high, indicating high environmental pressure. The emergy currency rate declined with a rise in the emergy investment rate, indicating economic growth. Additionally, the population carrying capacity was consistently > 1, indicating that the population was overloaded. Collectively, the emergy-based evaluation method of regional economic sustainable development in this study provides a comprehensive and scientific evaluation framework, which can help decision makers and researchers better understand and evaluate the problems brought about by the rapid development of regional economy, and provide targeted decision making suggestions. It includes four sub-systems: natural, economic, social, and sustainable, which have important theoretical and practical significances, while also serving as a useful reference for the evaluation of the sustainable economic development of similar regions.