Provided is a method of producing a transdermal absorption sheet having a stable shape with a simple apparatus configuration. The method of producing a transdermal absorption sheet includes a drug solution filling step of filling needle-like recessed portions 15 of a mold 13 having the needle-like recessed portions 15 with a drug solution 22 that is a polymer solution containing a drug, a drug solution drying step of drying the drug solution 22 filling the needle-like recessed portions 15 to form a drug layer 120 containing the drug, a polymer layer forming solution supply step of supplying a polymer layer forming solution 120 to the mold 13, the mold 13 being provided with a step portion that is higher than a region 16 in which the needle-like recessed portion 15 is formed in a periphery of the region 16 in which the needle-like recessed portion 15 is formed, at a height equal to or higher than a height of the step portion in a range of equal to or greater than the step portion as seen from above, and a polymer layer forming solution drying step of drying the polymer layer forming solution 24 supplied to the mold 13 to form a polymer layer 122.
