Life history of the mealybug, Paracoccus marginatus Williams and Granara de Willink, on two potted plants papaya (Caricapapaya L.) and brinjal (Solanum melongena L.), and one weed species (Parthenium hysterophorus L.) was studied under laboratory conditions. Mealybugs were able to develop, survive and reproduce on all three hosts; however, there were differences in the life history parameters. Adult females that developed on papaya emerged one day, two days earlier than those that developed on brinjal and parthenium plant, respectively. Mode of reproduction was sexual. Pre-reproductive and reproductive periods of the females were little lower on papaya plant 4.7±0.71 and 6.2±0.82 day, respectively, than other two host plants. Female: male ratio was maximum on brinjal (2.57: 1) and this ratio was almost near to mealybug reared on parthenium plant (2.54: 1). Mean fecundity of 291 ± 33.31 eggs on papaya was higher than on the other two plant species.