The purpose of the present invention is to provide an injectable vaccine composition that is safe and useful as a prophylactic or therapeutic agent for cancer or infectious diseases and can safely and effectively induce a systemic immune response. An injectable vaccine composition that is to be administered by injection to human or animals, characterized by comprising at least one kind of antigen and a lipopolysaccharide or a salt thereof as an immunostimulator, said lipopolysaccharide being derived from at least one kind 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, Zavarzinia, Pseudomonas, Achromobacter, Bacillus, Methanoculleus, Methanosarcina, Clostridium, Micrococcus, Flavobacterium, Pantoea, Acetobacter, Zymomonas, Xanthomonas and Enterobacter.