For the soft foundation covered with deep miscellaneous fill which is widely distributed in the suburban area,vacuum preloading construction technique is introduced.Adopting three improved construction technology including diversion hole,surrounding site sealing and diaphragm protection,the disturbance caused by deep miscellaneous fill is conquered,and vacuum preloading is implemented smoothly.The monitoring and testing data for the settlement,pore pressure,vane shear test and geotechnical laboratory test reveal that the strengthening effect is remarkable and the vane shear test strength increases by 67%.The construction technique achieves success in the engineering case,thus it may serve as reference for similar projects.