Abstract: A simple, rapid and sensitive spectrophotometric method for the determination of ni-ckel was described. It is based on the formation of a red violet complex between Ni(Ⅱ) and 5-Cl-PADAB in the presence of an amphotoric surfactant AES at pH 7.4—8.4, Beer's law is obeyed in the range of 0—15 μgNi/25ml. The molar ratio of Ni(Ⅱ) to 5-Cl-PADAB in the complex has been established as 1:2. The interference from metal ions was exa-mined.