Dendropsophus triangulum, commonly known as the triangle treefrog, is a species of frog in the family Hylidae.
It is native to the Amazon Basin of Brazil, Ecuador, and Peru, but may also be present in Colombia.

Distribution and habitat: Dendropsophus triangulum is known from Brazil (Acre, Amazonas, and Pará), Ecuador (Orellana and Sucumbíos), and Peru (Cusco and Loreto) at altitudes of above sea level. It can be found in primary and secondary tropical rainforests, around temporary ponds in clearings near forests, and in aquaculture ponds.

Ecology: Dendropsophus triangulum reproduces in temporary water bodies, with tadpoles developing in water after hatching from eggs laid on leaves.