Abstract: Thiobacillus ferrooxodans (T.f) were domesticated in in-situ leaching uranium mine and the effects test of coexisting ions such as SO^2-₄、NO^-₃、Cl^-、Zn²⁺、Cu²⁺、Mn²⁺、Cr³⁺、U、F^- etc.in solution on T.f activity have been investigated.The test results showed that the order of influence of different ions on bacteria activities was F^-＞U＞Mn²⁺＞Cr³⁺＞Zn²⁺＞Cl^-＞NO^-₃＞SO^2-₄ and the tolerant concentrations to SO^2-₄、NO^-₃、Cl^-、Zn²⁺、Cu²⁺、Mn²⁺ and Cr³⁺ were 32g·L^-1、3.2g·L^-1、3.2g·L^-1、0.40g·L^-1、3.2g·L^-1、0.40 g.L^-1 and 0.40g·L^-1 respectively and the most tolerant concentrations of ions were not still obtained.The tolerant concentration to U was 0.80g·L^-1.When the concentration of U was 1.60g·L^-1,bacteria lost activities and could not oxide Fe²⁺ to Fe³⁺.The bacteria activities were affected by F^- intensively.The tolerant concentration to F^- was only 20mg·L^-1.Domesticated bacteria have been used in field test of in-situ uranium leaching in Xinjiang.