I describe previously unknown begging calls and displays of a fledgling Rusty-breasted Cuckoo (Cacomantis sepulcralis) fed by a Pied Fantail (Rhipidura javanica) in Singapore. The cuckoo emitted two types of begging calls: (1) ‘host-absent begging call’ (loud ‘tsi’ repeated at 1-sec intervals) and (2) ‘standard’ begging call in the presence of the Pied Fantail (wheezy ‘seeee’ repeated 1–2 times/sec). The fledgling also performed the ‘wing-shake begging’ display, i.e., it raised one of its wings at a time towards the approaching Pied Fantail. This display was similar to that of the best studied brood parasite, the Common Cuckoo (Cuculus canorus). The structure of both types of begging calls of the Rusty-breasted Cuckoo was different in comparison to the Common Cuckoo and relatively more similar to some other closely related species of the genus Cacomantis.