In this study, utilizing the salt tolerant gene E3 ubiquitin ligase HERC2 sequence in sunflower which acquired previously, we constructed the transient expression vector Cam35SHERC2GFP. Subcellular localization was carried out by transforming onion epidermal cells with particle bombardment. The expression analysis, that of root, hypocotyl and leaf between the salttolerant hybrid P50 and the saltsensitive hybrid P29 under 120 mmol·L^-1 NaCl stress, was done by RTqPCR. Plant expression vector pPZP221HERC2 was constructed. HERC2 was transferred into tobacco to verify salttolerant functionality by Agrobacteriummediated. The results showed that: (1) subcellular localization showed that HERC2 protein expressed in cell membrane, cytoplasm and nucleus; (2) the expression of HERC2 gene was upregulated between the salttolerant hybrid P50 and saltsensitive hybrid P29 under NaCl stress, but the expression quantity of the former is higher than that of the latter; (3) the salt tolerance of transgenic HERC2 tobacco was stronger than that of the wild type tobacco. The study laid a foundation for analyzing of salt tolerance mechanism in sunflower and breeding salttolerant cultivar.