Metal-based membranes have emerged as a promising solution, providing selective permeability and impressive durability. However, a comprehensive understanding of their environmental performance across their entire life cycle remains elusive. This research offers a comprehensive life cycle assessment (LCA) of electroless plated palladium alloy-based membranes for hydrogen separation. It evaluates the environmental impacts across various stages, from the synthesis of supports to the application of intermediate and selective layers. Key findings include the identification of alumina supports and graphite intermediate layers as having minimal environmental impacts, and the Pd–Cu membrane as the most sustainable choice among palladium alloy membranes. This research advances our understanding of the eco-friendly performance of palladium based H2 separation membranes, guiding the development of more sustainable hydrogen separation technologies.