Abstract: Rare metals germanium and indium are important strategic resources，they are commonly associated with lead-zinc ore or coal，and mainly extracted from zinc smelter slag and ash of burning coal.The content of germanium，indium and SiO2 is 126.00 g/t，358.00 g/t and 24.62% in zinc smelting slag with high silicon from a lead-zinc smelter in Yunnan.In order to high efficiently leaching the germanium and indium，acid-leaching technology was research.Results showed that the leaching rate of germanium and indium can reach 87.90% and 89.88% under the optimal conditions of grinding fineness of 81% -0.074 mm，sulfuric acid concentration 110 g/L，liquid-solid ratio of 3，stirring speed of 350 r/min，leaching temperature of 70 ℃，leaching time of 4 h.

Key words: Zinc smelting slag, Sulfuric acid leaching, Leaching rate of germanium and indium