Abstract:In order to improve the nitrogen fertility and wheat yield of saline soil, achieve the purpose of improving fertilizer, increasing yield and efficiency, a field experiment was conducted in coastal saline soil test site to study the reasonable fertilizer management suitable for coastal saline soil. The split plot experiment was conducted from 2017 to 2019, with three mixing ratio of available and slow-released nitrogen fertilizer (N: 225 kg/hm2), 100%∶0 (F1), 50%∶50% (F2), 30%∶70% (F3), were used as the main plots. Three organic fertilizer rates were set as sub plots: 6 t/hm2 (O1), 12 t/hm2 (O2), and 15 t/hm2 (O3), and no nitrogen application was the control (CK).The results showed that compared with other nitrogen and organic fertilizer treatments, the F3O3 treatment effectively reduced the salt content in the surface of saline soil by 0.7%~9.5%, reduced the content of nitrate and ammonium nitrogen in 20—100 cm soil layers by 1.3%~42.3% and 3.8%~44.3% respectively, which effectively reduced the nitrogen leaching out of the plough layer, increased the contents of available nitrate and ammonium nitrogen in plough layer by 16.6%~59.8% and 21.5%~60.4% respectively from the turning green stage to mature stage. And the F3O3 treatment significantly increased wheat grain yield, increasing by 5.9%~47.0% in 2018 and 8.3%~46.6% in 2019 compared with other nitrogen and organic fertilizer treatments. To sum up, in the coastal saline soil, the treatment of 70% slow-released urea and 30% available urea combined with organic fertilizer 15 t/hm2 could effectively reduce the soil salinity and nitrogen leaching, maintained the available nitrogen nutrients, and improved the nitrogen supply capacity of the surface soil and wheat yield. It was the reasonable fertilizer operation mode of nitrogen fertilizer combined with organic fertilizer in coastal saline soil which can be widely used to improve fertilization and soil fertility.