Abstract: The life history of birds dictates their activities and is crucial to population success. However, the life history traits of only one-third of the world's bird species have been described; the rest are poorly understood. We studied the breeding ecology of the Yellow-bellied Warbler (Abroscopus superciliaris) and documented reproductive information throughout the egg and nestling periods. The data included natural nest sites, nest components, nest size, egg laying dates and time, egg morph, egg size, clutch size, egg incubation, nestling brooding and feeding, nestling morph and growth, and reproductive outcome. This study provided particular information of breeding ecology that has not been reported before in the Yellow-bellied Warbler.