This article takes a coating production line as an example, uses industrial metabolism analysis method to quantitatively analyse its material metabolism process, and forms a material balance sheet to evaluate resource efficiency and environmental efficiency. The results show that the resource efficiency of the coating production line is 0.4%, and the environmental efficiency is 0.51%, indicating that there is a serious waste of resources and greater environmental pressure. The reason is the old spraying method, the use of highly volatile paints and cleaning agents, and the higher VOC content of the paint. In response to these problems, this article combines the input and output content of the production line and proposes several green optimization approaches from the perspectives of cleaner production, circular economy and ecological industrial parks.