A transdermal absorption preparation precursor 50 containing a release liner 10 containing one first valley fold part 1, one or two first mountain fold parts 2, and a first base line L1 and a second base line L2 on one side and the other side apart from the first valley fold part 1 as a line of demarcation and at an approximately equal distance from the first valley fold part 1, wherein at least one of the first base line L1 and the second base line L2 is a fold line of the first mountain fold part 2, and a drug-containing layer 3 having a center line laid on the first base line L1 and an adhesive layer 4 having a center line laid on the second base line L2 on the release liner 10.
