Abstract: ‘Yayaohulu’ was used as the experimental material, and the treatment method of 85 mmol·L^-1 salt stress was used to study the alleviating effects of different concentrations of sodium nitroprusside(0.01,0.05,0.10,0.25,0.50 mmol· L^-1) on salt stress of ornamental gourd, in order to provide reference for exogenous nitric oxide to alleviate the damage of salt stress to gourd seedlings.The results showed that when the concentration of sodium nitroprusside was 0.10 mmol·L^-1,the net photosynthetic rate, transpiration rate and stomatal conductance of Lagenaria siceraria under NaCl stress were significantly increased, the chlorophyll content and soluble sugar content were promoted, the activities of antioxidant enzymes（SOD,APX and CAT） were promoted, the plant height, dry and fresh welight, root length（Len）,surface area（SA）,volume（Vol） and root tip number（NTips） of Lagenaria siceraria were increased, and the contents of ketone compounds, phenolic compounds and lignin were increased.With the gradual increase of sodium nitroprusside concentration, these indexes showed a trend of first increase and then decrease.0.10 mmol·L^-1 sodium nitroprusside significantly decreased free proline content, decreased malondialdehyde（MDA） accumulation, maintained cell swelling pressure and improved osmotic regulation of cells and the environment.Correlation analysis of photosynthetic fluorescence parameters, Pn, E,Gs, Fm, Fv/Fm, PI abs, psi（Eo） and other seven parameters were positively correlated, with the increase of nitrate concentration showed a trend of first increased and then decreased, Fo, DIo/RC and other two parameters were negatively correlated, with the increasing of sodium nitroprusside concentration showed a trend of first decreased and then increased.