The international standard of water footprints (ISO 14046) was published in 2014 based on life cycle assessment (LCA), which is defined as the index for quantifying potential water-related environmental influences. Based on the principle, requirements, and methodology of ISO14046, the aim of the present study was to introduce methods for calculating and evaluating water footprints, and analyze copper and aluminum alloy cables in relation to this. We evaluated the influence of water during the life cycles of the two cable types. Unlike the water footprint network (WFN), which emphasizes the calculation of the total requirement of water resources for production, the ISO method focused on the environmental influence assessment during the product life cycle. The case study indicated that the water consumption and footprint of the copper cable were lower by 24.8 and 97.9%, respectively, than that of aluminum alloy cable during their life cycles. This is because the water stress index (WSI) of Jiangsu Province, where copper cables are produced, is lower than that of Hebei Province, where aluminum alloy cables are manufactured. Therefore, the water usage for cable production in Jiangsu will influence the local water environment considerably less than in Hebei. Adopting scientific methods to evaluate the water footprint and quantify the environmental influence accompanying the full life cycle of industrial products provides a scientific basis for effective planning of the industrial distribution and sustainable utilization of water resources in our country.