Abstract: Sugar beet was cultivated in the hydroponic experiment to investigate the effects of the different Na+ concentrations on plant growth, physiological and biochemical character and nutrient absorption of sugar beet seedlings. The results show that the height, dry weigh of sugar beet seedlings, and leaf area (except 9 mmol/L), relative water content, activities of GPX and CAT of leaves increased, while water potential of leaves decreased when the Na+ concentrations were 0.75-9 mmol/L. Na+ promoted capacity of water absorption and preserving of sugar beet seedling. Relative water content of leaf raised, water potential of leaves, MDA content of leaves and electrolyte conductivity of leaves reduced, activity of SOD remained unchanged, activities of GPX and CAT were promoted, absorbed dose of nutrient elements of N, P, K were unchanged when the concentration of Na+ was 3 mmol/L. 3 mmol/L Na+ in the 1/2 Hoagland nutrient solution was best to stimulate the growth of sugar beet seedlings.