Abstract: Abiotic stresses such as salinity and drought can reduce crop yield and affect crop quality. Phosphoglucomutase（PGM） is a key enzyme in biological metabolism, which is mainly involved in sucrosemetabolism and starch synthesis in plants, and plays an important role in regulating plant growth and development. Studies have shown that PGM gene may play a specific role in plant abiotic stress response, but there is no report on how PGM gene responds to stress. This study obtained transgenic Arabidopsis thaliana with overexpression of A. thaliana PGM（AtPGM） through Agrobacterium mediated genetic transformation. The phenotype of the transgenic A. thaliana was compared with that of pgm mutant and wild type（Col-0）, and the role of AtPGM in regulating plant salt tolerance was investigated. The results showed that:（1） Overexpression of AtPGM in A. thaliana significantly reduced plant resistance to salt stress, and the survival rate of overexpression lines under salt stress was significantly reduced, while the salt tolerance of pgm mutant was significantly enhanced;（2） Under salt stress, the expression level of anthocyanin synthesis gene in pgm mutant was higher than that in overexpressed and wild type plants, and the phenotype showed significant accumulation of anthocyanin in leaves;（3） Malondialdehyde and hydrogen peroxide content in leaves of overexpressed lines increased significantly under salt stress, but significantly decreased in pgm mutants;（4） Compared with the wildtype, the germination rate of pgm mutant lines under salt stress was significantly increased, while the germination of overexpression lines was significantly inhibited by salt;（5） Further studies on the expression changes of ABA synthesis, metabolism and signal transduction genes under salt stress showed that the expression of ABA synthesis gene ABA1 and ABA signal transduction gene ABI5 increased significantly in pgm mutants, suggesting that the improved salt tolerance of pgm mutants may be partly due to the accumulation of ABA. These results indicate that pgm mutants have high salt tolerance, and AtPGM transgenic A. thaliana is significantly more sensitive to salt stress. AtPGM may be involved in the response of A. thaliana to abiotic stress by regulating redox homeostasis. This study lays a foundation for subsequent functional studies of AtPGM gene, and also provides candidate genes for stress resistance gene engineering improvement.