A simplified liquid-solid extraction technique was studied for the analyses of pesticide residues in soil samples. It is a simple, one step sample preparation method based on a relative quantification concept. Linear response curves were obtained for all of the target compounds regardless of their surface adsorption. This observation was explained and modeled to obey Langmuir adsorption Equation. The adsorption of analytes onto the sample surfaces will sacrifice the detection sensitivity. The strategies to reduce the surface adsorption, such as, molecular replacement and selection of solvents, were discussed. The relative quantification and the wide varieties of available solvents would enable the technique to be a useful method for the monitoring and analyses of pesticide residues in soils.