To enhance the flattening strength of at least the outdoor end of a sheath pipe or a vicinity thereof.

In a foundation penetrating piping part structure in which the sheath pipe 37 penetrating through the foundation 34 of a building 21 is provided and piping 38 is inserted inside the sheath pipe 37, the sheath pipe 37 has a flattening strength enhancing portion 46 preventing at least the end 37d of the sheath pipe 37 on an outdoor side 36 from flattening under the curing load 45 of concrete 34b constituting the foundation 34.