Herein, coordination polymer nanobelts (CPNBs) were preparedrapidly and on a large scale, by directly mixing aqueousAgNO3 solution and anethanol solution of 4, 4′-bipyridine at room temperature. The application of such CPNBs as a fluorescentsensing platform for nucleic acid detection was further explored. CPNB is aπ-rich structure,the strong π–π stacking interactions between unpaired DNA bases and CPNB leads to adsorption offluorescently labeled single-stranded DNA (ssDNA) accompanied by 66% fluorescencequenching. However, the presence of target ssDNA will hybridize with the probe. Theresultant helix cannot be adsorbed by CPNB due to its rigid conformation and theabsence of unpaired DNA bases. Thus, a significant fluorescence enhancement,73% fluorescence recovery, was observed in DNA detection as long as the targetexists. The present system has excellent sensitivity; a substantial fluorescenceenhancement was observed when the concentration of the target was as low as 5 nM. Italso exhibits outstanding discrimination ability down to a single-base mismatch.