A transdermal patch and a microneedle sheet 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 comprises a sheet-shaped base material and a plurality of microneedles on the sheet-shaped base material making contact with a stratum corneum of a skin. Each of the plurality of microneedles includes a skin-stretching part projecting from the sheet-shaped base material, the skin-stretching part having a tip surface configured to stretch the stratum corneum by pressing against the surface of the stratum corneum of the skin without sticking into the surface of the stratum corneum. A needlelike-projection part is formed on the tip surface of the skin-stretching part having a shape such that the needlelike-projection part sticks into the surface of the stratum corneum and a peak part of the needlelike-projection part stays inside the stratum corneum.
