Abstract: The optimization tests of zinc activator were carried out with a germanium-bearing sphalerite ore in Guizhou. The comparative tests were carried out with the novel inorganic activator X-43 and the traditional activator copper sulfate. Under the optimal conditions of lime dosage of 1 500 g/t, X-43 activator dosage of 700 g/t and collector dosage of 150 g/t, the grade and recovery of zinc in zinc concentrate were 52.87% and 67.24% respectively, and the grade and recovery of germanium were 715.30 g/t and 63.36% respectively. Compared with the use of copper sulfate, the zinc grade obtained by using X-43 increased 0.83 percent, and the zinc recovery increased 4.27 percent; the germanium grade increased 8.4 g/t, and the germanium recovery increased 6.79 percent. The results showed that compared with the traditional activator copper sulfate, the novel activator X-43 has stronger activation ability and better selectivity.