An object of the present invention is to provide a carrier composition for nucleic acid delivery, which can efficiently deliver a nucleic acid into cells when a nucleic acid such as siRNA is administered to animal-derived cells or animals, and also has low toxicity and high safety, and a composition for nucleic acid delivery containing the carrier composition and nucleic acid. A carrier for nucleic acid delivery is prepared by using (A) a diacylphosphatidylcholine, (B) at least one member selected from the group consisting of cholesterol and derivatives thereof, and (C) an aliphatic primary amine. Also, a composition for nucleic acid delivery is prepared by mixing the carrier for nucleic acid delivery with a nucleic acid.本發明之目的在於提供一種核酸送達用載體及含有該載體與核酸之核酸送達用組成物，該核酸送達用載體於將siRNA等之核酸投予源自動物之細胞或動物時，可使核酸有效地送達到細胞內，不僅低毒性且具高安全性。本發明係組合(A)二醯基磷脂醯膽鹼、(B)選自膽固醇及其衍生物所構成群組中之至少1種及(C)脂肪族第1級胺並加以配合而調製出核酸送達用載體。此外，將該核酸送達用載體與核酸混合，調製出核酸送達用組成物。
