We describe the nest of the endemic Whitehead's Spiderhunter (Arachnothera juliae) from Mt. Mulu National Park, Sarawak, Malaysian Borneo, and compare it to those of the most closely related species, the Yellow-eared Spiderhunter (A. chrysogenys) and the Naked-faced Spiderhunter (A. clarae). The nest was found on 3 August 2014 in lower montane forest at 1,400 m elevation along the summit trail on the western slopes of Mt. Mulu. It consisted of a bowl lined with fine bark material inside a naturally occurring hanging ball of moss 19 m above the ground in a large tree. It contained no eggs, but the pair was observed carrying in nest materials on several occasions.