The invention provides an integrated capillary-penetration underground well core and belongs to the field of ground source heat pumps. The integrated capillary-penetration underground well core comprises a low-water-permeability backfill layer and a high-water-permeability backfill layer which are sequentially arranged from top to bottom, wherein the high-water-permeability backfill layer is provided with an open type U-shaped pipe, the open type U-shaped pipe is provided with a low-position permeation pipe and a high-position permeation pipe, the upper ends of the low-position permeation pipe and the high-position permeation pipe penetrate the low-water-permeability backfill layer and extends into a soil layer above, the lower end of the high-position permeation pipe is provided with a high-position opening, a high-position capillary-penetration component is arranged on the periphery of the high-position opening, the low-position permeation pipe penetrates the high-position capillary-penetration component, a low-position capillary-penetration component is arranged on the periphery of a low-position opening in the lower end of the low-position permeation pipe, and at least one water-tight concrete module is arranged between the low-position capillary-penetration component and the high-position capillary-penetration component. The integrated capillary-penetration underground well core is high in heat exchanging efficiency, low in investment cost, and the like.