In this research, a near-IR fluorescent labeled nucleic acid conjugate for the nucleic acid detection was synthesized, and characterized preliminarily for the detection of the nucleic acid. Th conjugate combines the molecular recognition properties of the oligonucleotides with the near-IR fluorescence label PR646. Both single- and dual- labeled conjugates were studied for their hybridization with the complementary nucleic acid. The dual labeled conjugate has indicated that the self-quenching effect exists in ssDNA form while the fluorescence increases greatly after hybridization with the complementary nucleic acids. The time-resolved fluorescence was also studied.