In this paper, we provide for the first time a detailed description of the breeding ecology of the Masked Laughingthrush Garrulax perspicillatus. Our findings indicate that this species is a cooperative breeder with retained offspring. Flocks of Masked Laughingthrushes occurred in winter; these split into smaller breeding groups during the spring. The size of breeding groups varied from three to six individuals (mean = 3.8 individuals, n = 26). Clutches were initiated between early March and early August. Clutch size averaged 3.3 eggs and ranged from two to five (n = 18). The incubation period lasted on average 13.2 days (n = 9) and chicks left the nest after 12 days (n = 23). Breeding groups produce 2–3 broods per year (n = 2). 82.8% of 58 breeding attempts resulted in fledged offspring. Helpers were observed participating in nest-building, incubation and provisioning. The size of breeding groups was significantly related to both the overall frequency of feeding trips to the nest and brood size at fledging, with a higher frequency of feeding trips and more fledglings for larger groups. Hence, both breeders and helpers may potentially derive fitness benefits from helping at the nest.