6 strains of Pyropia yezoensis (Ueda)M.S.Hwang et H.G.Choi were analyzed using SRAP(sequence-related amplified polymorphism)markers in order to identify the germplasm.DNAs from conchocelis of 6 strains were screened with 35 primer combinations,of which 11 primer combinations gave stable and reproducible amplification patterns.Among the total 131 fragments,125 fragments(95.42%)were polymorphic.The genetic distances of 6 strains were between 0.364 3 and 0.867 9,and the average was 0.593 0.Cluster analysis of UPMGA showed a good and true relationships among the 6 strains.The results demonstrated that SRAP could be a useful tool in germplasm identification of P.yezoensis strains.From the total 131 fragments,4 fragments amplified by 1 primer combination were used to develop the DNA fingerprints of 6 strains of P.yezoensis.One specific fragment of TM-18 was obtained in the fragments amplified by primer combination ME1/EM6.According to the DNA sequence of the fragments,a specific pair-primer was designed and it achieved stable amplification of a 340 bp specific band in both DNA of conchocelis and blades of TM-18.The specific marker could be used in fast identification of TM-18 strain.