Provided are a transdermal patch and a microneedle sheet, which can efficiently introduce a target substance to the stratum corneum and prevent a reduction in the protection capability of the stratum corneum. A microneedle sheet (20) comprises a sheet-shaped base material (21) and a plurality of microneedles (50) on the sheet-shaped base material (21) making contact with a stratum corneum (110) of a skin (100). Each of the plurality of microneedles (50) includes a skin-stretching part (51) projecting from the sheet-shaped base material (21), the skin-stretching part having a tip surface (51 a) configured to stretch the stratum corneum (110) by pressing against the surface of the stratum corneum (110) of the skin (100) without sticking into the surface of the stratum corneum (110). A needlelike-projection part (52) is formed on the tip surface (51a) of the skin-stretching part (51) having a shape such that the needlelike-projection part (52) sticks into the surface of the stratum corneum and a peak part (52a) of the needlelike-projection part (52) stays inside the stratum corneum (110).
