Acetylcholinesterase (AChE) was purified on columns with iminodiacetate Agarose charged with Cu2+, Zn2+, and Ni2+. The best results (a 14-fold purification and more than 30% activity yield) were obtained with Zn2+ used as a complex-forming metal. The preparation had a specific activity of approximately 7 U. Its purity was tested by polyacrylamide gel electrophoresis under denaturing conditions.