Abstract: Selenium is a non-metallic element with certain electrical conductivity. It is mainly produced as an associated mineral. More than 90% of its production comes from anode slime produced by electrolytic refining of copper. Its supply capacity is restricted by the production capacity of the main metal（refined copper）. With the rapid expansion of strategic emerging industries such as photovoltaics, electronics and infrared, selenium, as one of the key raw materials for industries such as solar cells, optical glass and stainless steel, has become increasingly important in China’s resource security system. However, the existing research on the evolution trend of selenium supply and demand is relatively weak. This paper constructs a framework for China’s selenium resource demand forecast and supply potential assessment, using the ARIMA model to predict the selenium demand of seven major industrial sectors from 2024 to 2040. Combined with the copper-selenium co-associated characteristics, the S-curve is used to deduce the demand for refined copper, thereby estimating the primary supply capacity of selenium resources, and then judging the future supply and demand change trend. The results indicate that: ①China’s selenium resource production has continued to grow with the increase in refined copper production capacity in the past decade, but demand in traditional consumption areas has declined, showing a periodic oversupply. ②Selenium consumption structure is shifting from traditional industries such as metallurgy and glass products to photovoltaic thin film cells, infrared optical materials and other industries. The expansion of strategic emerging industries is accelerating, and emerging industries will become the main driving force for future demand growth. ③In the medium and long term, the supply and demand pattern of selenium resources will change from “supply exceeds demand” to “demand exceeds supply”, and the supply and demand gap will expand from 30 t in 2030 to 932 t in 2040. Based on these findings, this study recommends enhancing the resilience of China’s selenium supply chain through supply diversification, industrial upgrading, and the establishment of strategic reserves.The research results can provide scientific reference for ensuring the sustainable development of China’s selenium resource supply chain.