Single drop microextraction is one of the popular liquid phase microextraction technique. This method is inexpensive, easy to use and nearly solvent free. In this research, direct immersion single drop microextraction was coupled with corona discharge ion mobility spectrometry for the determination of diazinon pesticide in the water samples. The affected parameters on extraction efficiency such as type of extraction solvent, volume drop, stirring speed, ionic strength, pH, extraction temperature and extraction time were studied and optimized. The limit of detection and limit of quantification were obtained 0.7 and 2 ng/ml, respectively. The linear calibration ranged from 2–100 ng/ml with = 0.998. The relative standard deviations of the method were calculated 6% (intra-day) and 4% (inter-day). Environmental water samples was satisfactory applied as spiked samples and relative recovery values were obtained 90–108%.
