Mountainous terrain covers 60% of the land area of Hong Kong, and landslides may happen under conditions of continuous rainfall. Civil Engineering and Development Department of Hong Kong SAR Government has been building rigid concrete barriers and flexible wire-mesh fence along the hillside to protect the residential area below. However, these barriers are often located at remote area, making it difficult to perform onsite checks for accumulation of debris and determine if debris exceed the capacity limit of barriers. Smart landslide detection system provides real-time monitor of water level, falling debris and build up, and real-time alerts to the authorities concerned. The system performs steadily under extreme weather conditions, demonstrating its ability to immediately notice any landslide activity and protect residents.