The utility model provides a building foundation encryption device, include with foundation soil complex body, the body adopts first body, second body and the third body that fastens connecting deviceand connect in proper order including from top to bottom, first body surface is equipped with and prevents building foundation encryption device is torsional to prevent twising reverse the structure,the second body includes radial dimension degressive body from top to bottom, be equipped with a water -permeable structure in the third body. Prevent twising reverse the structure through the setting, can prevent that whole removal and structure of installing underground in the soil body from shifting, the second body has the inner wall of slope, provides bigger reaction force can for the encryption soil body, makes the encryption soil body take place bigger compression under certain of subsiding. A water -permeable structure not only can discharge and encrypt the moisture in the soil body and make the moisture penetration among the foundation soil encrypt the soil body, plays the effect that improves foundation soil matter, can prevent again that it oozes out to encrypt the soil body, guarantees encryption effect.