Biodegradation is a promising tool for complete destruction of organic pollutants present in the environment. Organophosphorus compound (OPs) like methyl parathion (MP) is widely used as pesticide in agricultural as well as non-agricultural fields. The pesticides of organophosphorus type is less bio accumulative and more readily degradable in the environment. The present study was focused on the biodegradation of methyl parathion pesticide using soil bacteria. Among the several bacterial isolates from soil, three species identified as Pseudomonas aeruginosa, Enterobacter sp and Klebsiella sp. The growth of these pesticide degrading bacteria was assessed in nutrient broth. The experimental study was conducted to investigate the efficiency of the chosen bacterial species on the degradation of methyl parathion and its effect on bacterial growth. The degradation of the pesticide was tested in three concentrations like 100 ppm, 200 ppm and 300 ppm. Among the three bacterial species used for degradation of methyl parathion at different concentrations, maximum degradation was observed by Pseudomonas aeruginosa at a temperature of 350C at pH 7 in 59 hrs at 300 ppm concentration. The degradation products of all the three bacterial samples were characterized by FTIR, HPLC and GC-MS.