The present invention relates to the nucleic acid complex expressed by formula 1. Formula 1: (In formula 1, X is an oligonucleotide, L1 and L2 each independently represents a sugar ligand, and S1, S2 and S3 each independently represents a linker).本發明係關於下述式1所表示之核酸複合體。式1:(式1中,X為寡核苷酸,L1及L2分別獨立為糖配體,S1、S2及S3分別獨立為連結子)