The present invention provides polynucleotides that can specifically hybridise to Hepatitis B virus (HBV) nucleic acids from all genotypes. These polynucleotides can be used in genotype-independent detection and quantitation of HBV nucleic acids. For example, the polynucleotides can be used as primers and/or probes in amplification-based assays for either end-point detection or real-time monitoring of HBV nucleic acids in a test sample. The polynucleotides can additionally be provided as part of a kit for the detection and quantitation of HBV nucleic acids.