The slopes at the north of Uludağ, where there is an unplanned and dense settlement, have landslide potential in terms of engineering geology. In this study, the causes of the landslide occurring as a result of the uncontrolled excavation carried out on the slope with landslide potential and the improvement or control studies were investigated. With the disturbance of the slope stability, settling and deformations on the upper part of the slope increased, and then 8 decares of area was affected by the flow and sliding mass movements on the slope, and approximately 80 houses in this section were evacuated for safety purposes. As a result of the researches and investigations made in the landslide field, an engineering geology model is revealed Geotechnical properties of geological units and the depth of slip surface were determined by the field and laboratory studies. Prevention and support projects are prepared according to geotechnical properties. As a first measure within the scope of the project, the construction of the support structure consisting of double rows of bored piles in the toe cut was then controlled by the production of a three levelled support structure. This study is a typical example where uncontrolled excavations without consideration of engineering geology and geotechnical conditions cause serious costs and other grievances.