Because animal eggs are quite rich in nutrients and easy prey for carnivores, to think the process of food chain in the ecosystem, egg predation will be an important aspect. Japanese forest green treefrog, Zhangixalus arboreus, is medium-sized arboreal frog endemic to Japan. On branch end of tree around pond, it lay eggs in foam nest made from its liquid secretion. Interestingly, foam nest is sometimes constructed on ground around the pond. How does such oviposition site flexibility affect predation of this frog's eggs? Arboreal site is obviously superior in terms of predation avoidance, but main animals that consume foam nests on the tree as well as on the ground are still unclear. To address this issue, we set censor cameras to monitor the arboreal and terrestrial foam nests. Based on the videos, we checked predator species and predation risk at each oviposition site of this frog. As a result, predation pressure on the arboreal foam nest was very low, and only one foam nest was consumed. A scene where raccoon, Procyon lotor, and Japanese marten, Martes melampus, failed to climb tree branch attached with the arboreal foam nest was recorded. On the contrary, terrestrial foam nests were consumed by Japanese field mouse (Apodemus sp.), raccoon and the marten frequently (almost one quarter of total 101 observation night). Especially, the mouse was main predator of this frog's eggs because it accounted for more than 80% of predation. These facts show that terrestrial site is subject to higher predation risk than arboreal site. Thus, oviposition site flexibility of this frog is evidently connected with egg predation risk of eggs. Decision of terrestrial oviposition also can be interpreted as creating prey-predator relationship between frog eggs and carnivores such as the mouse, raccoon, and the marten,　and it decreases hatching rate of eggs. As a result, in case of terrestrial oviposition, fewer hatchling flow into the pond. Thus, there is differential energy flow in ecosystems compared with the case of arboreal oviposition. Those our findings will contribute to understanding relationship between oviposition site and food chain in waterfront animal community.