Provided are a transdermal absorption sheet capable of achieving control of the dissolution rate and suppression of diffusion of a drug, and a method of producing the same. A transdermal absorption sheet 100 includes a sheet portion 116, and a plurality of needle-like protruding portions 110 formed by a plurality of frustum portions 114 arranged on the sheet portion 116 and needle portions 112 arranged on the frustum portions 114, in which at least one of the needle-like protruding portions 110 has a cavity portion 124 extending from the sheet portion 116 to the frustum portion 114.
