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嗜酸性氧化亚铁硫杆菌（Acidithiobacillus ferrooxidans）是铜矿生物冶金中应用最广泛的微生物之一。但在冶金过程中淋滤出来的Cu2＋等重金属逐渐积累,达到一定的浓度后就会抑制A.ferrooxidans的生长,从而降低冶金的效率。本文着重研究了Fe2＋初始浓度对A.ferrooxidans耐铜性的影响。实验中ρ（Cu2＋）变化范围为0～5.0 g/L。结果表明,当ρ0（Fe2＋）为6.7 g/L时,A.ferrooxidans仅在Cu2＋为0～0.4 g/L的体系中能显著地氧化Fe2＋进行生长;当Cu2＋≥0.5 g/L时,A.ferrooxidans生长完全受到抑制。将ρ0（Fe2＋）增加到8.9 g/L,A.ferroox-idans在0.5、1.0、2.0和3.0 g/L Cu2＋的培养基中也能明显氧化Fe2＋,并最终将其完全氧化,Cu2＋对A.ferrooxidans生长抑制作用仅出现在4.0和5.0 g/L Cu2＋的体系中。因此提高体系中亚铁离子的浓度能提高菌体对Cu2＋的耐受力。研究结果对铜矿的生物冶金具有重要意义。“,”Acidithiobacillus ferrooxidans is one of the key microorganisms exploited in copper bioleaching process.However the accumulated Cu2＋ from bio-hydrometallurgy will inhibit the growth of A.ferrooxidans and thus greatly decrease the efficiency of bioleaching.In this study,the impact of ρ0（Fe2＋） on copper（Cu2＋） tolerance by A.ferrooxidans was investigated.No growth was observed in the systems with ρ0（Fe2＋）=6.7 g /L when ρ（Cu2＋） was ≥0.5 g/L.However,when ρ0（Fe2＋） was increased to 8.9 g/L,growth was observed in 3.0 g/L Cu2＋ amended systems and Fe2＋ conld be completely oxidized.Thus the tolerance of Cu2＋ by A.ferrooxidans is closely related to the ρ0（Fe2＋） in the systems.This result has great significance in copper bioleaching practice.