Rhacophorus arvalis is a species of frog in the Rhacophoridae family endemic to Taiwan. It is a medium-sized tree frog; females are up to 6.5 cm (2.6 in) in snout-vent length, and males are much smaller. Its natural habitats are subtropical or tropical moist lowland forests, intermittent freshwater marshes, arable land, plantations, rural gardens, and irrigated land. It is threatened by habitat loss. Conservation measures include maintaining traditional agricultural practices.