Abstract: DNA damage of mulberry（Morus alba） leaf detected by RAPD marker technology could be used as a reference for evaluating the salt tolerance of mulberry. After treated by 02% and 04% NaCl solution for 8 weeks， mulberry genomic DNA was isolated for RAPD assay. After using 16 RAPD primers to amplify the genomic DNAs of three samples， 59 clearly distinguishable bands were obtained， 3.69 bands per primer on average. Calculation with Ntsyspc 2.1 software displayed that the genetic similarity coefficients between DNAs from different treatments were in the range of 03662-0.5476. The result of dendrogram showed that the samples treated with 0.2% and 0.4% NaCl solution were clustered into one group， and the normal sample was clustered into one group. These results showed that NaCl concentration has positive correlation with DNA damage of mulberry leaf， and the degree of DNA damage in mulberry leaf can be an effective reference of selecting salt\|enduring mulberry varieties.

Key words: salt stress, mulberry（Morus alba）, DNA damage, random amplified polymorphic DNA