Breeding biology of Red vented bulbul (Pycnonotus cafer) was studied in the areas of Rawalpindi and Islamabad. A total of 45 nests were located in the study area out of which 35 nests were found active. Majority of successful nests (43%) were in the fork of trees followed by middle of the trees (29%) and on the top (11%) of the trees. Preferred nest height (53%) by red-vented bulbul was 1-2 meters from the ground. Vegetation material used for nest building by Red-vented bulbul was Beri (Zizyphus nummalaria) (31%) followed by Guava (Psidium guajava) (22%), Sheesham (Dalbergia sissoo) (18%), Snatha (Dodonea viscosa) (16%) and Date palm (Phoenix dactylifera) (13%). Highest percentage (51%) of nests was found with clutch size three followed by clutch size two and four. Predation rate was only 6% in eggs and 9% in nestlings. Breeding success in the present study was evaluated as good which was 82% and 86% for eggs and fledglings, respectively. Loss of nesting sites due to urban expansion and pollution negatively affect the population of Red - vented bulbul.