Customer demand variability is one of the most severe issues that lead to an imbalance between demand and supply. Therefore, demand forecasting is crucial in supply chain management because it provides potential trends, changes, and meaningful insights to eliminate uncertainty and stabilize the supply chain. Accurate demand forecasts have a significant impact on supply chain performance. In this chapter, we examine and compare the effect of demand forecasting techniques on environmental performance in the Vietnamese coffee supply chain context. We find that LSTM outperforms ARIMAX in terms of carbon and water footprint. As a result, advanced demand forecasting techniques are a valuable investment. However, managers and organizations need to consider several vital dimensions when implementing them. We provide some practical insights into the roles of demand forecasting techniques and issues that organizations may face.