Abstract: The systemtic relationship of 20 species large bryophyte were generated using RAPD method.Seven primers were screened from 200 random primers，and a total of 82 DNA fragments were amplified，79（96.34%）of which were polymorphic.The average number of DNA band produced by each primer was 11.71.Neis similarity coefficients were calculated with the software of NTSYSpc version and dendrogram of 20 species bryophyte was constructed using UPGMA.20 kinds of bryophyte were divided into two genus at 0.27 genetic similar coefficient.They were Sphagnum and Bryum.20 kinds of bryophyte may be divided into four genus at 0.42 genetic similar coefficient.They were Sphagnum including 1 species，Acrocarpi-Haplolepodeae including 2 species，Acrocapi-Diplolepideae including 6 species and Pleurocarpi-Diplolepideae including 10 speices.Bryiidae were divided three clusters.Sphagnum was a primitive cluster，Polytrichum was a evolutive cluster.The result was in accordance to most of the classified system of the bryophyte classical taxology.

Key words: bryophyte, systemtic relation, genetic similar coefficient