Many reports have described that non-human primates capture and consume vertebrate prey. However, the colobinae monkeys with more strict phytophagous diet rarely prey on vertebrates. We recorded an adult female Rhinopithecus roxellana preyed on three Chinese Babax’s (Babax lanceolatus) chicks from a nest in Shennongjia National Park on Sept. 7, 2018. The monkey killed all the three chicks by biting off their heads while feeding on them. In this case, multiple individuals, most were female juveniles, were involved in watching the process of predation and actively explored the inside of the nest. The significance of this case is not only to further understand the feeding habits of R. roxellana, but also to accumulate basic data for exploring the behavioral mechanism of primate’s carnivority.