A transdermal administration device includes an administration section which includes a substrate having a first surface and a second surface which is a surface opposite to the first surface, and a projection protruding from the first surface, the administration section having flexibility； and a support body having a support surface that supports the second surface, the support body having flexibility. The support body includes at least one low rigidity region and at least one high rigidity region having flexural rigidity higher than flexural rigidity of the low rigidity region, the support body being configured to satisfy at least one of requirements that the low rigidity region is sandwiched by two high rigidity regions to form a stripe and that the high rigidity region is sandwiched by two low rigidity regions to form a stripe.
