The invention provides an oligodeoxynucleotide containing humanized K type CpG oligodeoxynucleotide and poly deoxyadenylate, wherein the poly deoxyadenylate is placed on the 3'-side of the humanized K type CpG oligodeoxynucleotide. In addition, the present invention provides a complex containing the aforementioned oligodeoxynucleotide and B-1, 3-glucan.