Abstract: Indonesia is one of the tropical countries located on the equator which has high and sometimes tendency to be extreme rainfall characteristic. Average rainfall in all regions of Indonesia ranges from 3000-3500 mm per year. This phenomenon causes Indonesia become a landslide prone country. Several cases of landslides have occurred in the Semarang city, especially in Simongan area. Almost every year a landslide occurs in Simongan area and it always causes a lot of losses. The purposes from this study was to figure out the geotechnical properties of soil and conduct field investigation on the triggers of landslide and mechanism of landslide analysis in the study area. In the area, the soil was composed of silt and clay. To complete all data used in the analysis, field and laboratory testing were conducted.