Abstract: Pseudomonas putida was isolated from organophosphate contaminated soil by enrichment method. Dimethoate optimally was degraded at 0.8 g L-1 in mineral solution and showed the maximum tolerance at 4 g L-1 in nutrient broth. Dimethoate was degraded two folds more than orthophosphate. Total protein was increased to 287 mg L-1 in single culture. Anti-acetyl choline esterase (AChE) Activity was proportionally displayed of dimethoate level (0.2-2 g L-1). Dimethoate (2 g L-1) was remedied 50 and 100% by p putida after 48 and 96 h, correspondingly. It means that its anti-AChE effect diminished to 70-95%. The strains were lost the dimethoate degrading plasmids by 200 mg L-1 of acridine orange and converted to dimethoate-sensitive strains. This plasmids were transferred to sensitive strains that were consecutively confirmed by replica plating technique in mineral medium containing dimethoate. We are supposed to simply applying organophosphate degrading plasmids for cleaning the anti-nerve agents.