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A greenhouse experiment was conducted to evaluate phytotoxicity and distribution of Cu in a tropical soil amended with sewage sludge (Sw) and copper sulfate (CuSO 4 .5H 2 O). Samples of a clay soil from the State of Paraná, Brazil were collected at depth of 0-20; 20-40 and 40-60 cm, and brought to the laboratory to be properly accommodated in experimental units (PVC tubes). The Cu treatments were performed by the application of Sw (10 t ha -1 ) amended with Cu (SB-T), and by CuSO 4 . H 2 O (WB-T). Lettuce plants were cultivated in the amended soil in order to predict the toxicity of the Cu. The experiment was conducted for 70 days, and then the lettuce plants and soil samples were collected for analysis. A sequential method was used to separate soil Cu into following fractions: exchangeable, amorphous iron oxide bound, crystalline iron oxide bound, organic matter bound and residual bound. The experimental results showed that Fe, Zn, K, P, Cu and organic matter amounts of the soil increased with the treatment SB-T. The toxic phyto-available Cu content in the soil for the lettuce plants was 80.00 mg kg -1 . A percolation study showed that the Cu contents were larger for the first 20 cm of depth, indicating that the metal was not transported down the soil profile. The Cu content of different fractions declined in an order residual > amorphous iron oxide > crystalline iron oxide > organic matter > exchangeable, regardless of treatment performed. Additionally, the Cu contents added from treatments were determined mainly in amorphous iron oxide fraction.