Industrial ecology offers an original way of looking at economic activities. The approach is based on an analogy between certain objects studied by the science of ecology (ecosystems, metabolisms, symbiosis, biocenosis, etc.) and industrial systems. However, this analogical relationship raises difficulties due to the various interpretations to which it is open. Although there is agreement regarding its heuristic function, the analogy can nevertheless be understood either as a model or as a metaphor. The present article first attempts to show how models differ from metaphors. It then sets out to justify the epistemological relevance of this distinction for industrial ecology research. The reflection should thus contribute to clarifying the debate on the (supposed or desired) role of analogy in the field of industrial ecology and heighten the interest this field of investigation represents for implementing sustainable development.