To provide an immunopotentiating agent that has a more potent activity than previously known CpG-SPG complex.SOLUTION: The present invention provides a pharmaceutical composition that contains a complex containing an oligodeoxynucleotide containing humanized K type CpG oligodeoxynucleotide and poly deoxyadenylate placed on the 3'-side of it, and β-1,3-glucan, the pharmaceutical composition used (1) for the prophylaxis or treatment of virus infection, cancer, an allergic disease, or intracellular parasitic protozoan or bacterial infection or (2) for immunopotentiating.SELECTED DRAWING: None【課題】従前のCpG-SPG複合体よりも強力な活性を有する免疫賦活剤を提供すること。【解決手段】ヒト化K型CpGオリゴデオキシヌクレオチド及びその3’側に配置されたポリデオキシアデニル酸を含むオリゴヌクレオチドと、β-1,3-グルカンとを含む複合体を含有する医薬組成物であって、(1)ウイルス感染症、癌、アレルギー疾患、細胞内寄生性原虫又は細菌感染症の予防又は治療、あるいは(2)免疫賦活化のための、医薬組成物。【選択図】なし