Rhombophryne vaventy is found in montane rainforest at high altitude (~ above sea level) on the Marojejy massif. Like most Rhombophryne species, R. vaventy is a terrestrial or possibly semi-fossorial frog. It is a generalist predator, and its diet is known to include relatively large arthrosphaerid pill millipedes of the genus Zoosphaerium. Nothing is currently known of its breeding or calling behaviour.