Abstract: An entomological study of Anopheles species was conducted to find the seasonal variation of prevalent vectors to establish their correlation with the malaria parasite in Quetta. Vector collection was done according to World Health Organization standards of surveying. Analyses reveal the predominantly rapid increase in density of Anophles stephensi in rural areas, over Anophles culicifacies. The changing pattern of vectors in rural area must be due to some strong factor, which could obviously be attributed to the migration of million of Afghan refugees living mostly in the suburbs of Quetta.