Sixteen different soils，representative of the soils of China，were selected and sampled for an experiment on toxicity of extraneous copper to tomato growth. The samples were amended with CuCl₂ to obtain a range of eight concentrations. Tomato shoot growth (21 d) test was performed in unleached and leached soils under controlled environment conditions. The results showed that the values of EC₅₀，which were the concentrations of Cu added to soils that made tomato shoot biomass down to 50%，were increased significantly in leached soils，especially the three soils high in organic carbon and the two soils high in salinity. Partial correlation analysis showed that soil pH was the most important factor controlling Cu toxicity to tomato growth. Stepwise multiple regressions showed that soil pH and organic carbon content could explain more than 80% of the variance for EC₅₀ values in both leached and unleached soils. When taking into account the effect of soil clay content in unleached soils or the effect of cation exchange capacity in leached soils on EC₅₀ values，determination coefficients (R²) of the regression models were increased up to 0.862 and 0.891，respectively. Findings of the experiment demonstrate that it is proper to use some soil properties，like pH，organic carbon content，clay content or cation exchange capacity as indicators to predict the toxicity of extraneous copper in the soil to tomato growth.