) Abastract: Nuclear ribosomal DNA (nrDNA) has been considered as an important tool for inferring phylogenetic relationships at many taxonomic levels. Based on molecular clone and sequencing analysis on one unique copy of nrDNA ITS region in Nothotsuga longibracteata, the structural characteristics of pseudogene were studied. Moreover, we discussed the molecular mechanism of pseudogenization. The results showed that the length of pseudogenic copy was 1745 bp, and was 11-12 bp shorter than that of others. The GC content of pseudogenic copy was significantly lower. Especially, GC content were 6.15～6.17% in 5.8S region and 5.75～6.15% in the ITS2 region lower than that of others. The marked sequence distance between pseudogenic copy and others were 0.0718 + 0.0221 in 5.8S and 0.0691 + 0.0178 in ITS2 respectively. Phylogenetic analyses indicated that a unique position was in the phylogenetic trees with long terminal branch length.