The Quinalphos and Cypermethrin molecules are being used alone and a combination as an effective insecticide successfully in the agriculture and domestic area of application. Both the molecules (Quinalphos and Cypermethrin) being used large quantity in the environmental application and the residue of these insecticide has to be controlled by applying a required quantity with in dissipation time of these molecules. These molecules are also toxic to humans and animals hence the lowest concentration also has to be detected for monitoring and controlling purpose. A simple HPLC analytical method; in a single run both the molecule was detected at 0.4mg/L concentration. With the Apollo Silica 5µ (250 mm × 4.6 mm) HPLC column; acetonitrile and water as a mobile phase with ration of 80:20 (volume/volume) at 1.5 ml/min. flow rate. The detection wavelength is 316 nm for Quinalphos and 278nm for Cypermethrin were detected by the PDA detector of Shimadzu LC2030 model HPLC. The results of the analysis deliver that the proposed RP-HPLC method is simple, rapid, precise and accurate, which is useful for the identification and quantifications of these molecules interims of validation parameters viz., separation, system suitability, System Precision and linearity in a simple HPLC analysis.