Abstract: The main characteristics of deep filled foundation in hilly-gully regions are complicated topographic and geomorphic conditions,complex geological environment,accompanied with large area of collapsible loess and soft alluvial soil,massive earthworks volume,various influencing factors and limited construction period.The problem of stabilization,sedimentation,drainage,slaking distortion-controlling,slope protection and so on is involved in the construction of loess high fill foundation.The practice in dealing with the problem of the deformation and stability of deep cut and deep filled foundation in the hilly-gully regions of loess plateau are introduced by taking typical projects for example.The construction methods consist of comprehensive evaluation of engineering geological conditions,optimizing the excavation-fill balancing,constructing the effective underground water drainage system,reinforcing of the original foundation soil by dynamic compaction,compacting(or dynamic compacting) of the loess filling,effective treatment of the fill slope and the cut slope,controlling the construction with quality inspection by three-dimensional method,and evaluation of the deep filled foundation condition by geotechnical engineering monitoring throughout construction period etc.The key techniques can also be used to similar projects as reference.