Abstract:Eleven isolates of virulent Newcastle disease virus (NDV) prevailing during 2002~2007 from chicken flocks in Shanghai were collected. The F gene of these viruses were cloned and sequenced. Their sequences were submitted to GenBank,and accession numbers were as follows:NDV 022433(EU258661),022435(EU258662),0210149(EU258653),0210154(EU258654),0210227(EU258656),0210252(EU258658),03024(EU258637),04011(EU258639),05013(EU258640),07011(EU258642) and 07023(EU258643),respectively. The results of sequence analysis showed that the F gene fragments from 11 NDV isolates consisted of l 654 bp,coding for 551 amino acids.The homologies of nucleotide and deduced amino acid sequence among the 11 NDV isolates were 94.6%~100% and 93.0%~100%, respectively. The sequences of cleavage site of F protein were 112R-R-Q-K-R-F117, all of the 11 isolates belonged to the genotype Ⅶ virulent NDV. There had the nearest distances among the 11 isolates as compared with that of the NDV vaccine strains(B1,La Sota,V4 and F48E9) by the phylogenetic tree. In addition,they had two RsaⅠ sites at position 973 and 1 249 nt which are characteristic to most strains of goose origin.