The purpose of the present invention is to provide a vaccine pharmaceutical composition for transdermal administration that is safe and useful as an agent for the prevention or treatment of cancer or infection, it being possible to safely and effectively induce a systemic immune response using this vaccine pharmaceutical composition. The present invention is a vaccine pharmaceutical composition for transdermal administration to be administered to the skin of a human or animal, wherein the vaccine pharmaceutical composition for transdermal administration includes: a lipopolysaccharide or salt thereof derived from at least one type of gram-negative bacterium selected from the group consisting of Serratia, Leclercia, Rahnella, Acidicaldus, Acidiphilium, Acidisphaera, Acidocella, Acidomonas, Asaia, Belnapia, Craurococcus, Gluconacetobacter, Gluconobacter, Kozakia, Leahibacter, Muricoccus, Neoasaia, Oleomonas, Paracraurococcus, Rhodopila, Roseococcus, Rubritepida, Saccharibacter, Stella, Swaminathania, Teichococcus, Zavarinia, Pseudomonas, Achromobacter, Baccillus, Methanoculleus, Methanosarcina, Clostridium, Micrococcus, Flavobacterium, Pantoea, Acetobacter, Zymomonas, Xanthomonas, and Enterobacter, as an immunopotentiator; and at least one type of antigen, the mass ratio of the immunopotentiator and the antigen (total mass of immunopotentiator/total mass of antigen) being 0.002-500.