Improved ventilating insole structure

Provided is an improved ventilating insole structure comprising an upper insole having a forefoot provided with air vents, a lower insole, and a foam pad sandwiched between the two insoles and having a shape slightly smaller than that of upper and lower insoles. The upper insole is formed with an accommodation trough on a bottom surface thereof and a circumferential wall around the accommodation trough. The foam pad is shaped to fit in the accommodation trough. The circumferential wall is configured to enclose the foam pad and the lower insole. The circumferential wall close to a heel portion of the upper insole is provided with a notch with an arbitrary shape. The notch is adapted to receive a foam lug extending from the foam pad or to receive one or a plurality of air guide pipes to prop up the upper and lower insoles at the notch. In operation with an air outlet of a shoe, the foam lug or the air guide pipe can extend outward as an air passage for fresh air to flow in or out of the shoe so as to circulate air. When a person wearing the shoe walks or runs, with the help of pressing and loosing of the forefoot and heel one by one, inner and outer air exchange of the shoe is fully supplied, providing a comfortable and dry effect.