To investigate the effects of different base topdressing rates of nitrogen (N) fertilizer on the activity of key enzymes of N metabolism, N accumulation and transport, yield and N fertilizer utilization in drip irrigated spring wheat under N reduction mode, and to provide a scientific basis for the efficient production of drip irrigation spring wheat in Xinjiang wheat area, with medium gluten Xinchun 6 (XC 6) and strong gluten Xinchun 37 (XC 37) as materials, five nitrogen base topdressing ratios of 0∶0, 2∶8, 3∶7, 4∶6 and 5∶5 were set to study the effects of nitrogen base topdressing ratio on nitrogen metabolism and nitrogen use efficiency of spring wheat under drip irrigation. The results showed that, with increasing N fertilizer basal rate, nitrogen metabolism enzyme activity, nitrogen accumulation, nitrogen fertilizer utilization rate (NUE), seed yield and protein yield all tended to increase and then decrease, while pre-flowering nitrogen translocation rate, pre-flowering nitrogen contribution rate, and nitrogen fertilizer physiological utilization efficiency (NPE) showed the opposite trend, and the above parameters were higher in XC 37 than XC 6 at the same N fertilizer basal rate. The interact of variety and N fertilizer basal chase ratio showed that pre-flowering N translocation, post-flowering N accumulation, post-flowering N contribution, NUE, N fertilizer agronomic use efficiency (NAE), N fertilizer partial production (NPEP), N harvest index (NHI), seed yield, and protein yield were increased by 1.51%~34.93%, 10.62%~83.63%, 4.82%~25.38%, 8.00%~45.11%, 6.97%~19.84%, 2.00%~5.80%, 7.95%~40.38%, 1.44%~84.86%, 4.44%~98.04%, respectively, under 3∶7 treatment compared to the rest of the treatments. Correlation analysis showed that NUE was significantly and positively correlated with protein yield, seed yield, plant nitrogen accumulation, GS, and NR. Therefore, a 3∶7 ratio of nitrogen fertilizer base topdressing could improve plant nitrogen accumulation and promote seed yield, protein yield and nitrogen utilization based on the increase of nitrogen metabolizing enzyme activity.