Until now most ornithological work on Borneo has been carried out in the Malaysian part of the island (the states of Sarawak and Sabah) and in coastal areas of Kalimantan, Indonesia (Mann 2008). e northern interior of the province of Central Kalimantan, in common with many other inland and montane areas of Kalimantan, has received little attention. Among the only published information is a series of reported sightings from short visits to this area by Holmes & Burton (1987) and a later detailed study on the Busang and Murung rivers by Wilkinson et al.(1991). Results from these surveys led to the declaration of the Ulu Barito Important Bird and Biodiversity Area (IBA), as designated by Birdlife International (2014) based on the presence of globally threatened, rangerestricted and biome-restricted species (criteria A1, A2 and A3). No further surveys in this part of Central Kalimantan were carried out until very recently (Woxvold & Noske 2011, van Berkel et al. 2012, Cheyne et al. 2012) and these have improved our knowledge of the biodiversity of the region. In this paper we build on these earlier studies by presenting the results of an avifaunal inventory of Bukit Batikap Protection Forest. is is the most northerly part of the Ulu Barito IBA that has been surveyed to date. e Bukit Batikap Protection Forest is located entirely within Murung Raya district of Central Kalimantan province and is part of the Muller-Schwaner mountain range that forms the central spine of Borneo and from which all major rivers originate. It is a 456,000 ha area of almost undisturbed tropical rainforest, surrounding the headwaters of the Joloi and Busang rivers, two major tributaries of the Barito River. Elevations range from 100m to 1,580 m. Forest vegetation at lower elevations is dominated by trees of the Dipterocarpaceae family, resulting in mixed dipterocarp forests typical of the interior of Borneo. At around 200 to 350m the forest type changes to hill forest characterised by reduced diversity of dipterocarp trees. is type of forest was encountered up to 750m. Patches of kerangas (heath forest on peaty soils) were rare in the area. e Ulu Barito IBA is protected for the purpose of watershed conservation and logging is prohibited here. erefore, the vast majority of the forest is in primary condition, although a few large timber trees have been illegally felled in areas close to rivers. Strips of riparian forest are present along all rivers, as well as secondary regrowth from historical crop cultivation. e local populace from small villages outside the protected area enter to collect products of commercial value, including gaharu (Agarwood Aquilaria malaccensis), gold, swilet nests, fish, and other wildlife for meat and the pet trade, as well as body parts. e forest is the site of an orangutan reintroduction project with over 130 Bornean Orangutans Pongo pygmaeus reintroduced by the Bornean Orangutan Survival Foundation (BOSF) by late 2014 (Husson et al. 2015). e objective of our avifaunal inventory was to describe the bird diversity of the area and, to a lesser extent, to understand the breeding and migratory behaviour of the species present.