A field experiment was carried out in coastal mudflat in Yancheng of northern Jiangsu Province to study the coupling effects of salt and fertilizer application on the growth and ion distribution of oil sunflower in 2008. The results were as follows: ① Compared to S1 treatment (the salt concentration of soil was 1.3-1.6 g/kg), there was no significant decrease of seed yield under S2 treatment (the salt concentration of soil was 2.9-3.6 g/kg). The seed yield decreased with an increase of salt concentration of soil under S3 treatment (the salt concentration of soil was 5.9-6.8 g/kg). The seed yield increased with the increases of N and P additions, and the effects of N and P increased with an increase of salt concentration of soil. ②Na+ and Cl－contents in root, stem, leaf and disc increased significantly with the increase of salt concentration of soil but K+ and Ca2+ changed slightly. ③Under the same concentration of soil salt, Na+ and Cl- contents in root, stem, leaf and disc all decreased with the increase of N and P additions while K+ and Ca2+ increased. The results showed that nutrient ions were further absorbed and transported selectively and the harmful ions of salt were further restrained with the application of nitrogen and phosphorus. It is an effective way to increase saline tolerance and seed yield of oil sunflower by the use of nitrogen and phosphorus in the coastal mudflat of northern Jiangsu.