Abstract: ObjectiveThe physiological response of Aquilaria sinensis seedlings to sodium nitroprusside(SNP)-acid aluminum(AlCl3)interaction stress were analyzed to provide theoretical basis for further studying the resistance mecha-nism of A. sinensis against AlCl3stress.MethodA completely random design was applied,A. sinensis seedlings were stressed by different concentrations of AlCl3and treated with SNP-AlCl3interaction.Physiological indexes such as photo-synthetic pigment and soluble sugar content of A.sinensis under different treatment were detected.Fuzzy analysis method of membership function was used for comprehensive evaluation.ResultPhotosynthetic pigments,soluble sugar content and soluble protein content in the seedling leaves of A.sinensis reached the maximum under 0.2 mmol/L AlCl3stress,and were the minimum under 0.8 mmol/L AlCl3stress. Malondialdehyde(MDA)content were the lowest when under 0.2 mmol/L AlCl3stress,and were the highest when under 0.8 mmol/L AlCl3stress,while activities of superoxide dismutase (SOD),peroxidase(POD)and catalase(CAT)were on the contrary.After adding SNP the physiological indexes in A.si-nensis seedling leaves such as contents of chlorophyll a,chlorophyll b,carotenoid,soluble sugar and soluble protein activi-ties of SOD,POD,CAT were largely higher than those without SNP.Correlation analysis indicated that,for the indexes in-cluding contents of total chlorophyll,chlorophyll a,chlorophyll b,carotenoid,soluble sugar and soluble protein,activities of SOD,POD and CAT there were extremely significant positive correlation between one and another(P<0.01).Conclu-sionApplying low concentration(less than 0.2 mmol/L)AlCl3solution promotes A.sinensis seedlings growth.Exogenous addition of SNP has obvious mitigative effects on the toxicity caused by high concentration(0.8 mmol/L)AlCl3stress in A. sinensis seedlings,which can be applied in the related field such as cultivation and resistance research of A.sinensis seed-lings.