A method was designed for the determination the amount of nickel in bronze. It was based on the adsorption of nickel on positive ion exchange of strong acid Amberlit CG-120 in form–H. HCl:acetone medium at pH=1 was used in order to separate other positive ions as chloride complexes. The fluids were filtered and the cation exchanger was treated with ammonium buffer solution pH=8-9, then it was treated with an ethanolic solution of Dimethylglyoxime. The determination of Nickel content was carried out using a spectrophotometer. Results indicated a content of 0.29±0.02%, whereas the nickel theoretical content was 0.31%. Using IR spectra, it was found that the adsorption of nickel on Amberlit CG-120 was due to covalent bonds with groups-SO3-, in the form of ammonium complexes.