A catalytic ozonation-microbial fuel cell and A ferroxidans leaching process was used in treating flotation wastewater to remove COD and heavy metals in this paper. The results indicated that when adding 1 g/L the manganese/modified activated carbon (Mn/GAC) catalyst and 1.5 g/min ozone flow, the COD could be degraded from 2,043.67 mg/L to 711.4 mg/L. After that, the COD could continue decreasing down to 72.56 mg/L through an air-cathode single chamber microbial fuel cell (SCMFCs) coated with 0.4 mg/cm2 platinum catalyst after 15 days. Meanwhile, the maximum voltages and the ultimate power density of the SCMFCs has reached 378.96 mV and 7,608.35 mW/m2, respectively. For filter residue, when 1.2 g/L Fe3+, 10% (m/v) filter residue, and 10% Acidithiobacillus ferrooxidans (A. ferrooxidans) were added, the copper leaching rate could reach 92.69% after 7 days if the pH values were adjusted to 1.9. Furthermore, the other heavy metals were also decreased to a level lower than the pollution control standard (Chinese standard, GB3838-2002). The leaching parameters in terms of pH, redox potential (Eh), and cyclic voltammetry were showed that the addition of an appropriate concentration of Fe3+ to the leaching systems was beneficial to copper dissolution.