This study conducts probabilistic tsunami hazard analysis (PTHA) based on a random phase approximation developed by Goda et al. (2016). The target area and event are the western Japanese Pacific coast and the Nankai-Tonankai Earthquake. The result of a Monte Carlo tsunami simulation shows a large variations of tsunami height depending on the earthquake source and bathymetry. Following the tsunami simulation, probabilistic tsunami heights are estimated in two different approaches: the random phase and logic tree model. It is confirmed that exceedance probabilities of tsunami height differ significantly by the models
