A field experiment was carried out on mudflat along the coast of Yancheng, Jiangsu Province to study coupling effect of salt and fertilizer application on growth and yield of Helianthus tuberosus in soils different in salt concentration in 2008. Results show (1) the plant decreased significantly in plant height with rising salt concentration of the soils and a similar trend was observed with diameter of its stem, and yields of its tuber and shoot, and however, it displayed a reverse trend in plant height and yields of tuber and shoot, with higher N and P application, but remained almost unchanged in diameter of the stem; (2) the positive effects of N and P additions on plant height was significant in all treatments and became more with rising salt concentration in the soils, and so were the effects on stem diameter, and yields of tuber and shoot; and (3) variance analysis revealed extremely significant correlations at the lever of F _0.05 and F _0.01 among soil salt concentration, application rate of N and P fertilizers, interaction between salt and fertilizer application and interaction between N and P applied. Through analysis of effects of soil salt, nitrogen and phosphorus in various treatments, the main factor that affected tuber yield was salt concentration of the soil, which was followed by fertilizers of N and P. And the yield of tuber was the highest in Treatment S1N2P3, of which the soil salt concentration was 0.9～1.5 g kg^-1, and the N and P application rate 60 kg hm^-2 and 60 kg hm^-2, respectively.