The main purpose of this thesis paper is to brief taxonomic study and biology of P.marginatus and to determine fluctuation and seasonal abundance of P.marginatus. Specific objectives are to find out damage potential of P.marginatus attacking leaves, immature and mature fruits of papaya and control measures of papaya mealybug. Finally find out the optimum doses of different biopesticides to prevent infestation of P.marginatus. Here Paracoccus marginatus is a dangerous insect pest causing worst damage to the agricultural, vegetable and various plants.