The species diversity of Dacinae fruit flies (Bactrocera spp.) was monitored in guava growing areas in various districts of western Uttar Pradesh, India, over a 12 months period (October, 2017- September, 2018). Samples of fruit flies were collected by using methyl eugenol lure traps and infested guava fruits collected from the farmer’s orchards in fruiting season. Three species of fruit flies recorded were, Bactrocera correcta, B. dorsalis and B. zonata. In general, proportionately higher population of B. zonata was recorded form various places surveyed. There was not much difference in species composition in different places. However, on an average, population differences were noticed in different areas. Number of adult fly emergence from the infested guava fruits collected from different places was proportionately in the range of , and for B. zonata, B. dorsalis and B. correcta, respectively. | Species complex of fruit flies, Bactrocera spp. (Diptera: Tephritidae) infesting guava in western Uttar Pradesh, India