Abstract: To evaluate the potential applications of somaclonal variation in potato（Solanum tuberosum L.），in this study we established regeneration systems of microtuber slices in Mira by regulating combinations of plant growth regulators and sucrose concentration. The line M-13 with excellent performance was quickly screened out from regenerated plants through stress treatment，and the study on its growth characteristics and phenotype stability was performed. The molecular markers start codon targeted（SCOT）and random amplified polymorphic DNA（RAPD）were used to analyze the genetic variation of M-13. The results suggested that the bud regeneration rate could reach 65.33% of the highest value in the medium MS + 2 mg ? L-1 6-BA + 0.25 mg ? L-1 TDZ + 0.1 mg ? L-1 2,4-D without sucrose. Both plantlet and microtuber weights of M-13 which grew stronger were about 2-fold compared with the mother plant Mira. The root/ shoot ratio and chlorophyll content of M-13 increased by 112%，23.78%，but the soluble phosphorus content and peroxidase（POD）activity in leaves decreased by 16.36% and 30.37%，respectively. The genetic similarity coefficient between M-13 and Mira analyzed by SCOT and RAPD markers were 0.9323 and 0.9256，which indicated that M-13 remains most features of mother plant Mira but occurred genetic variation.

Key words: potato, microtuber, regeneration system, somaclonal variation, new material