Field experiments were conducted to investigate effects of urea added with different fertilizer synergists(fulvic acid U17,polyaspartic acid U24,compound fertilizer synergist of fulvic acid and polyaspartic acid U20)on maize yield and nitrogen use efficiency.Results showed that compared with common urea,synergistic urea U20,U24 and U17 increased maize yield by 16.0%,8.5% and 8.0% respectively,and the differences arrived at significant level;Maize yield under the treatments of U20，U24，U17 with subtracting 20% didn’t decrease significantly.Compared with common urea,synergistic urea U20，U24 and U17 enhanced nitrogen use efficiency by 18.0,10.3 and 11.5 percentage points respectively.Nitrogen use efficiency under the treatments of U20,U24 and U17 with subtracting 20% were also increased by 18.6,12.7 and 12.3 percentage points respectively compared to common urea,and were higher than those of the treatments of full amounts.Among three fertilizer synergists,the effects of the treatment of compound fertilizer synergist of fulvic acid and polyaspartic acid(U20)was the best.