Zhangixalus prasinatus (common names: tributary flying frog, green treefrog, emerald green treefrog) is a species of frog in the family Rhacophoridae endemic to northern Taiwan.

[2] Z. prasinatus is the largest tree frog in Taiwan; the adult female frog can be 65 mm (2.6 in) to 77 mm (3.0 in) in snout-vent length.

This frog is green in color with a yellow stripe on each side and a white belly.

Its range includes at least one protected park: Hapen Nature Reserve.

Breeding takes place in tree holes, but also in cisterns, buckets, or water tanks.