Randomly amplified polymorphic DNA（RAPD） and inter-simple sequence repeats（ISSR） markers were used to evaluate the germplasm genetic diversity among 110 accessions of wild close relatives of barley（Hordeum vulgare L.）from the Qinghai-Tibet Plateau.30 RAPD primers and 10 ISSR primers were selected for PCR-amplification.The 30 RAPD primers and 10 ISSR primers generated 195 RAPD fragments and 93 ISSR fragments

respectively.The percentage of polymorphic loci was 93.33% for RAPD markers and 98.92% for ISSR markers.Therefore

ISSR markers were more efficient than the RAPD assay.Genetic Identity（GI） among different barley groups was very high computed by the software POPGNEN32.Based on RAPD markers and ISSR markers two UPGMA dendrograms were built.Both the dendrograms could divide the seven barley groups into two main clusters: one cluster containing all Tibetan barley groups except Nagri Prefecture in the ISSR dendrogram

while the barley group of Qinghai composed of another cluster.Therefore

these results showed the higher genetic diversity of barley in Tibet of China and also gave the further evidence to support the hypothesis that Tibet is one of the original centers of barley（Hordeum vulgare L.）.