The recovery of copper (Cu) from secondary sources has received much attention because of its scarcity of natural resources. In this work, we estimated the input, in-use stock and discard of copper and copper alloy during 1950–2015 in global scale, and forecast them until 2050. In addition, we estimated the potential of scrap recovery for copper/copper alloys. It was estimated that the total amount of in-use stock of copper and copper alloy were 177,000 kt and 44,200 kt in 2015, respectively. The in-use stock, discard and input of copper in 2050 will reach 381,000–588,000 kt, 15,400–22,200 kt and 18,990–33,000 kt, respectively, whereas those for copper alloy will reach 77,500–134,000 kt, 3,020–4,680 kt and 3,760–7,200 kt, respectively. The copper content in recoverable scraps of copper and copper alloy will reach 15,100–27,300 kt, and this accounts for 55.1–79.0% of copper content in annual input of copper and copper alloy in 2050. The range in forecast was caused by the difference in the saturation amount of in-use stock per capita and recovering rates of scraps. This Paper was Originally Published in Japanese in J. Japan Inst. Met. Mater. 82 (2018) 8–17. Reference 38) was added in order to more precisely explain.