Aglaia cucullata (Roxb.) Pellegr. is a less salt-tolerant tree species of Sundarban mangrove ecosystem. The present study was conducted to investigate the influence of salinity on the survival and growth ofA. cucullata seedlings and nutrient distribution in seedling parts. All (100%) the seedlings of A. cucullata was found to survive at non-saline to slightly saline (0 to 5 PSU) condition and no seedlings were survived beyond 15 PSU salinity. Seedling growth in terms of biomass, height and collar diameter showed a significant (p<0.05) negative relationship with the salinity gradient. The highest concentration of nitrogen (42 to 25 mg/g) and potassium (34 to 30 mg/g) was found at leaves. While roots contained the highest phosphorous (4 to 3 mg/g) and sodium (34 to 13 mg/g). However, nitrogen, phosphorous and potassium in different parts ofseedlings showed significant (p >< 0.05) negative correlations with the salinity gradient, while sodium showed a significant (p < 0.05) positive correlation. In conclusion, A. cucullata is very sensitive to salinity for survival, growth and nutrient distribution in their parts, and that the distribution of this species may be confined only in the less saline areas of Sundarban.