Birds are a major bio-indicator in a mountain-forest ecosystem. Avifaunal researches play an important role in formulating conservation plans. This avifaunal study was conducted in mt. Arayat (1026 masl); a dormant volcano situated in the centre of Pampanga's flat terrain. It intende4d to find out the diversity and abundance of avifauna in this unique mountain. Species recording was done from October 2018 to January 2019 using Point Count Method. A total of 66 avifaunal species were explored belonging to 39 families- consisting of various notable species such as: Montacilla alba (Montacilladae) a rare migratory species; Loriculus philippensis (Psittaculidae) and Phapitreron amethystinus (Columbidae) - critically endangered species, Otus megalotis and Ninox philippensis (Strigidae) - rare Philippine endemics, and various Migratory raptors, Accipiter soloensis (Accipitridae) and Pandion haliaetus (Pandionidae). Family Muscicapidae and Cuculidae appeared to be the most abundant avifaunal species. A breeding site of Haliastur indus (Accipitridae) was documented along the mountain's high altitude ridges (1,001 masl), which contributed to their abundance. Shannon-Weiner's Index denoted the very high avifaunal diversity (3.517) and high species evenness (0.5104). Species richness of the area is still partially based from the species discovery curve. Results have projected a glimpse of understorey rich biodiversity of the mountain, which may serve as basis for further studies and conservation efforts.