Abstract: This study explored the regulatory effect of exogenous gibberellin (GA₃) on the dormancy of Jasminum sambac during winter natural dormancy, to provide technical support for the commercial production of fresh-cut leaves of J. sambac in winter.J. sambac was used as the test material, with four treatments set up: 50, 100, 150 mg/L GA₃ and clear water control (CK). After a single foliar spray, growth indicators, photosynthetic parameters, and key physiological indicators were determined to analyze the concentration-dependent regulatory effects of GA₃. Exogenous GA₃ application in winter natural dormancy significantly promoted the growth and physiological activity of J. sambac, with significant concentration-dependent differences. Specifically, 150 mg/L GA₃ significantly increased the relative increment of plant height (17.98 cm), net photosynthetic rate (9.59 μmol·m⁻²·s⁻¹), and total chlorophyll content (1.71 mg/g), which could effectively break dormancy by enhancing photosynthetic efficiency. The 100 mg/L treatment had the highest ground diameter increment (1.18 mm), height-diameter ratio (11.65), and number of new branches (1.33), showing good effects on aboveground morphogenesis and fresh-cut leaf yield improvement. The 50 mg/L treatment significantly increased soluble sugar content and endogenous 6-BA content, which was suitable for optimizing the balance of endogenous hormones. GA₃ treatments at different concentrations promoted the aboveground growth, increased instantaneous photosynthetic parameters and endogenous growth-promoting hormone content to varying degrees, but had a certain inhibitory effect on plant biomass accumulation. For root activity, osmotic adjustment substance content and chlorophyll content, low concentration of GA₃ showed an inhibitory effect, while medium and high concentrations showed a promoting effect. Exogenous GA₃ application in winter natural dormancy can effectively break dormancy and promote vegetative growth of J. sambac. GA₃ at different concentrations has different regulatory focuses, and the suitable concentration can be selected according to the production target.