Objective To monitor the contamination rate and concentration of Norovirus in mussels sold in Beijing seafood market and to provide basic data for risk assessment of Norovirus in mussels. Methods The visceral mass of mussels were dissected and homogenized, Norovirus were extracted from visceral mass by adding PBS buffer and shaking 60 min. The Norovirus RNA was extracted and detected using commercial kit. Results Two hundred and ninety-three mussels samples were detected. The total positive rate was 9.22%(27/293). In all the positive samples, the gene group I accounted for 37.04% (10/27) and gene group II accounted for 62.96% (17/27). The range of the quantity of Norovirus in positive mussels was 6.20×10³-3.15×10⁵ gene copies/g (visceral mass). Conclusion The mussels sold in Beijing were contaminated by Norovirus.