Landslides in mountainous areas are the major source of sediment delivered to downstream areas and dominates the mountain erosion rates. Although the natural landslide is caused by heavy rainfall, earthquakes, volcanic activities, and so on. Rainstorms are the most common triggers for landsliding in most tropical mountainous areas especially in the north and south regions of Thailand. This purpose of this research is to assess the relationship between the probability of landslide and sediment yield in several regions of Thailand. For this research, the relationship between sediment yield and probability of landslide was develop using sediment yield observations from 36 stations over all of Thailand. The probability of landslide depends on the effect of topography, geology and hydraulic gradient due to rainfall variation by digital elevation data with 1 km resolution. The result shows that landslide events have significantly the effect on sediment yield in Thailand. Furthermore, we analyze the relationship between sediment yield and probability of landslide in several areas of study area consisting of north, south, northeast and central areas in Thailand. We found that the most of sediment yield in Thailand occurs in the northern and southern regions (landslide area) because these regions are covered by the mountain and steep slope area due to heavy rainfall in monsoon season.