Abstract: The ground treatment in Taiyuan area of northern Shaanxi is difficult because of thick deep-seated loess.Ted laboratory experiment reveals that the loess collapsibility correlates with loess structure,primitive water con-tent,void ratio,forming times,cause of formation and other factors.The collapsibility is gradually decreasing downwards.The water content and void ratio are correlated to loess collapsibility.It is suggested that the common ground treatment of the building with weight less than 250 kPa in Taiyuan area need adopt the construction in col-lapsible loess region,such as soil stratification and soil pipe or combined soil stratification and piles,but for buildings with weight larger than 250 kPa need adopt pile foundation construction.