To analyze the molecular biological characteristics of Norovirus from a gastroenteritis incident in Siming District.Methods Eleven anal swab specimens and one oyster samples were collected and fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) method was applied to detect Norovirus. The positive samples were amplified by RT-PCR, and amplified products were used for gel electrophoresis analysis and sequencing to determine the genotype and to make phylogenetic trees analysis. Results Two strains of GI Norovirus were detected from 11 anal swab specimens, and both were successfully sequenced. Four strains of GII were detected, and 3 strains were successfully sequenced. One strain of GI was detected from the oyster, and was successfully sequenced. Six positive strains successfully sequenced were further homology analyzed. The sequence of the GI.2 strain were highly homologous with the reference strains of KP325648 etc. collected from Shanghai in 2014. The sequence of GII.17 strain were highly homologous with the reference strains of KT384078 etc. collected from South Korea in 2015. GII.17 strain was reported for the first time in Xiamen.Conclusion The aggregated gastroenteritis incident was caused by mixed infection of GI.2 and GII.17 Norovirus.