The utilization of renewable energy and waste heat recovery can effectively alleviate the ongoing energy crisis and environmental pollution. The organic Rankine cycle has been proven to be reliable in converting low-to-medium-grade waste heat to power. The fluid selection is a crucial factor in the organic Rankine cycle design procedure, because the cycle performance depends mainly on the thermophysical properties of the working fluid. In this study, the optimal selection principle, based on environmental and economic criteria, for 14 different working fluids is proposed, considering a heat-source temperature range of from 90 to 230 °C. Electricity production cost and reduction of greenhouse gas emissions were selected as the objective functions. Through carbon footprint analysis, the greenhouse gas emissions generated by the organic Rankine cycle were investigated. Then, parametric studies were performed to analyze the matching relationship between the heat-source temperatures and corresponding fluids. The results demonstrate that for organic Rankine cycles with low-global warming potential (GWP) fluids, the construction phase generates the majority of the total emissions, approximately 66.24–90.21%. For high-GWP fluids, such as R134a and R245fa, the majority of the emissions are generated during the operation phase and include approximately 481.17 tons and 374.47 tons CO2,eq, respectively. From the viewpoint of environmental benefits, R600a exhibited the highest emission reduction, approximately 9531.06 tons CO2,eq, followed by R152a, R600, and R245fa, at a heat-source temperature of 150 °C. The matching relationship study indicated that the optimal temperature ranges for R601 are 363–384 K and 481–503 K, based on the maximum emission reductions. Regarding the economic analysis, the suitable temperature range corresponding to the best economic performance for R245fa was 363–468 K. Finally, correlations based on the best environmental benefits between the heat-source temperatures and optimal fluids were provided.