Reactivation by oximes was studied by using acetylcholine esterase (ACHE) immobilized on a cotton cloth and inhibited by organophosphate chemical warfare agents. The activity of ACHE was estimated by continuous measuring the remission changes of the cloth surface with immobilized ACHE by using the Ellman＇s method with acetylthiocholine iodide as substrate and 5,5＇-dithiobis(2-nitrobenzoic) acid as the chromogenic agent. The stable enzymatic chimera formed by immobilization of ACHE on the cotton cloth enables a simple isolation of the enzyme-inhibitor complex from the studied medium, in this case solutions of inhibitors and reactivators. ACHE, immobilized on cotton cloth can be recommended as a simple in vitro model for ACHE bound to cell membrane in in vivo experiments. The results obtained in this study with oximes and immobilized ACHE-oganophosphate chemical warfare agents enzyme-inhibitor complexes are in accord with the published facts concerning inhibition of ACHE by organophosphate chemical warfare agents and reactivation of enzyme-inhibitor complexes by oximes. The mentioned procedure enables a simple evaluation of the reactivation effect of oximes on a given enzyme-inhibitor complex. No significant differences were found between ACHE from bovine and human tissue nucleus caudatus.