A method of producing a transdermal absorption sheet comprising, in this order: a polymer solution filling step of filling needle-like recessed portions on a mold having the needle-like recessed portions arranged two-dimensionally with a polymer solution (24, 124); a polymer solution drying step of drying the polymer solution (24, 124) filling the needle-like recessed portions to form a polymer layer; and a peeling-off step of peeling off the polymer layer from the mold, wherein in the polymer solution drying step, low rate drying conditions are set in a concentration range in which an average solid content concentration of the polymer solution (24, 124) is 70 wt% or more and 80 wt% or less in terms of weight percent, and when a constant drying rate of water is used as an index, in the concentration range in which the average solid content concentration of the polymer solution (24, 124) is 70 wt% or more and 80 wt% or less in terms of weight percent, the constant drying rate is set to be lower than a maximum value of a constant drying rate under drying conditions in a concentration range in which the average solid content concentration of the polymer solution (24, 124) is less than 70 wt% and more than 80 wt% in terms of weight percent, wherein the constant drying rate of water under the drying conditions in the concentration range in which the average solid content concentration of the polymer solution (24, 124) is 70 wt% or more and 80 wt% or less in terms of weight percent is 0.10 kg/(h·m 2) or less, wherein a polymer contained in the polymer solution (24, 124) includes at least one of sodium chondroitin sulfate, hydroxypropyl cellulose, or dextran, and wherein a sheet portion average thickness after the polymer solution drying step is 50 μm or more and 500 μm or less. a polymer solution filling step of filling needle-like recessed portions on a mold having the needle-like recessed portions arranged two-dimensionally with a polymer solution (24, 124); a polymer solution drying step of drying the polymer solution (24, 124) filling the needle-like recessed portions to form a polymer layer; and a peeling-off step of peeling off the polymer layer from the mold, wherein in the polymer solution drying step, low rate drying conditions are set in a concentration range in which an average solid content concentration of the polymer solution (24, 124) is 70 wt% or more and 80 wt% or less in terms of weight percent, and when a constant drying rate of water is used as an index, in the concentration range in which the average solid content concentration of the polymer solution (24, 124) is 70 wt% or more and 80 wt% or less in terms of weight percent, the constant drying rate is set to be lower than a maximum value of a constant drying rate under drying conditions in a concentration range in which the average solid content concentration of the polymer solution (24, 124) is less than 70 wt% and more than 80 wt% in terms of weight percent, wherein the constant drying rate of water under the drying conditions in the concentration range in which the average solid content concentration of the polymer solution (24, 124) is 70 wt% or more and 80 wt% or less in terms of weight percent is 0.10 kg/(h·m 2) or less, wherein a polymer contained in the polymer solution (24, 124) includes at least one of sodium chondroitin sulfate, hydroxypropyl cellulose, or dextran, and wherein a sheet portion average thickness after the polymer solution drying step is 50 μm or more and 500 μm or less.