The present invention aims at providing a vaccine composition capable of being administered to an intraoral 
mucous membrane, ocular 
mucous membrane, ear 
mucous membrane, genital mucous membrane, pharyngeal mucous membrane, 
respiratory tract mucous membrane, bronchial mucous membrane, pulmonary mucous membrane, 
gastric mucous membrane, enteric mucous membrane, or rectal mucous membrane, that is safe, useful as a prophylactic or therapeutic agent for infectious diseases or cancers, and capable of effectively inducing the systemic immune response and mucosal immune response. The present invention provides a 
mucosal vaccine composition to be administered to at least one mucous membrane selected from the group consisting of a human or animal intraoral mucous membrane, ocular mucous membrane, ear mucous membrane, genital mucous membrane, pharyngeal mucous membrane, 
respiratory tract mucous membrane, bronchial mucous membrane, pulmonary mucous membrane, 
gastric mucous membrane, enteric mucous membrane, and rectal mucous membrane, the 
mucosal vaccine composition containing: at least one 
antigen; and as an 
adjuvant, a 
lipopolysaccharide derived from at least one 
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, Zavarzinia, 
Pseudomonas, 
Achromobacter, Bacillus, Methanoculleus, Methanosarcina, 
Clostridium, 
Micrococcus, 
Flavobacterium, 
Pantoea, 
Acetobacter, 
Zymomonas, 
Xanthomonas, and 
Enterobacter, or a salt thereof, wherein a 
mass ratio between the 
adjuvant and the 
antigen (total 
mass of the 
adjuvant / total 
mass of the 
antigen) is 0.002 to 500.