Abstract: Micro region burying bag tests were conducted to study the effect of slow- release nitrogen proportion on nitrogen use efficiency of maize specific fertilizer and spring maize yield, as well as that on saline-alkali soil environment, aiming to find out the suitable application proportion of slow-release nitrogen in north Shanxi. The results showed that the application of slow-release nitrogen could increase dry matter accumulation of maize and promote nitrogen uptake, significantly increase the yield of maize, and decrease soil pH value. Among them, the yield of 33% slow-release nitrogen treatment increased by 48.72% compared with that of urea treatment, nitrogen uptake amount and dry matter accumulation amount increased by 40.92% and 21.60%, respectively in mature period. The nitrogen use efficiency of spring maize significantly increased with the application of slow-release nitrogen, compared with the urea treatments, the use efficiency of 33% and 50% slow-release nitrogen treatment increased by 30.90% and 15.49%, respectively. After the application of slow- release nitrogen, pH value decreased by 0.45 units at most. In conclusion, under the experimental conditions, adding 33% slow-release nitrogen in maize specific fertilizer could match nitrogen release and nitrogen uptake of maize, ensure high yield and improve soil environment.