Experiments have been carried out on the extraction of nickel from ammonium sulphate aqueous solutions using LIX 54 as extractant, Nickel extraction decreases with increasing ammonium sulphate concentration of the aqueous solution. This decrease can be attributable to the formation of nickel ammine complexes in the aqueous phase thus decreasing the free nickel ion concentration. From the slopes of log D-NI versus equilibrium pH plots, the extracting species has been found to be NiR2, further, numerical analysis of experimental data confirmed the proposed stoichiometry and the corresponding log K-ext are given. The extraction of free metal ion by LIX 54 was also confirmed by IR studies of nickel loaded organic solutions.