The elevational gradient of Mt. Wilhelm, the highest peak in Papua New Guinea, represents one of the best-surveyed elevational gradients in the Indo-Pacific region. Based on field work undertaken in 2013 and 2015, we report range extensions, new elevational records and add 24 species to the list of bird species recorded along this gradient. This includes information on poorly known species such as Long-billed Cuckoo Chrysococcyx megarhynchus, Leaden Honeyeater Ptiloprora plumbea. Yellow-breasted Satinbird Loboparadisaea sericea and Sooty Shrikethrush Colluricincla tenebrosa.