Abstarct: In this research, solvent extraction process of zinc from sulphate solution obtained from the leaching of low grade sulphide-oxide samples was investigated using D2EHPA and Cyanex 272 diluted in kerosene in a batch reactor. The leaching liquor (aqueous phase) was achieved from ferric sulfate and sulfuric acid sulfate media. Response surface modeling (RSM) was employed to optimize the important parameters including stirring speed, sulphuric acid concentration, acid to ferric sulphate ratio, liquid to solid ratio and temperature. The optimum conditions were found to be a stirring speed of about 320 rpm, 1.14 mol/L sulphuric acid concentration, 2.5 acid/ferric sulphate ratio, 10 ml/g liquid/solid ratio and 80 °C temperature. Under these conditions, the highest recovery of zinc was achieved of approximately 94.3%. In solvent extraction experiments, various parameters such as pH, temperature, organic solvent concentration, organic phase to aqueous phase and time were investigated. According to the results, D2EHPA exhibited the higher extraction efficiencies than Cyanex 272 at the organic/aqueous ratio of 1:1. The optimum concentration and pH for D2EHPA and Cyanex 272 were distinguished to be 0.5 mol/L and 2.5, and 0.035 mol/L and 3.5, respectively. Under these conditions, extraction efficiency was found to be ~75% for D2EHPA against 41% for Cyanex 272. The plot of log D versus log [D2EHPA] was applied to determine the number of moles of D2EHPA participating in the extraction system. The plot confirmed the presence of 1 mole D2EHPA in dimeric form for 1 mole Zn in the extraction system. Thermodynamic data showed that the zinc extraction process is endothermic. The McCabe–Thiele diagram was also used to estimate the theoretical stages number of extraction, which the results showed that two stages are required to achieve the maximum extraction of zinc in an organic to aqueous phase ratio of 1. At the end of this research, a number of experiments were carried out to investigate the effect of the synergism system of Cyanex 272 and TBP with D2EHPA at the slightly lower concentration value of D2EHPA (0.2 mol/L). It was found that the mixture of 80% D2EHPA and 20% Cyanex 272 exhibited the best synergistic effect for Zn-extraction with a synergistic coefficient of 1.04.