To understand the possible influence of extreme rainfall events due to climate change on hillside disasters, this study on the assessment of regional rainfall-induced landslide hazards under extreme climate conditions in Keelung river watershed was conducted. First, rainfall data were collected to examine the spatial and temporal characteristics of rainfall in the study area. Then, the regional rainfall-induced landslide model was established based on the deterministic approach and used to simulate the extreme rainfall induced landslides in the study area. Finally, the prediction of landslide susceptibility could then be made using different return periods of 24-hour rainfalls. The results demonstrate this study could provide useful information for predicting the spatial distribution of areas susceptible to landslides and may mitigate hazards.