Abstract: As a precious native tree species in southern China, Mytilaria laosensis is widely cultivated, promoted, and utilized.To investigate the mitigating effect of nitric oxide (NO) on the growth inhibition of Mytilaria laosensis seedlings under acid-aluminum stress, half-year-old seedlings were used as experimental materials. A two-factor completely randomized block design was employed, with two SNP concentrations (0, 0.1mmol/L SNP) solution and five AlCl₃ concentrations (0, 0.2, 0.4, 0.6, 0.8mmol/L), resulting in 10 treatment groups. Seedling growth indicators were measured, and a comprehensive evaluation was conducted using the subordinate function method. The results showed that in the absence of SNP, the plant height, ground diameter, and leaf area of seedlings significantly decreased (P<0.05) with increasing AlCl₃ concentration. After the application of 0.1mmol/LSNP solution, plant height, ground diameter, leaf area, and total dry weight were significantly increased in all treatment groups.Among the treatments, T4 performed optimally, with plant height, ground diameter, and total dry weight increasing by 37.2%, 32.1%, and 38.4%, respectively, compared to the control. The seedling quality index (QI) reached 0.369. Subordinate function analysis ranked T4 first in the comprehensive evaluation. In conclusion, 0.1mmol/L SNP solution can effectively alleviate aluminum toxicity and promote the growth of Mytilaria laosensis seedlings. This study provides a theoretical basis for cultivating Mytilaria laosensis seedlings in acidified red soil regions of southern China.