Abstract: A field experiment of six treatments was conducted to improve fertilizer management in red date and cotton intercropping system. The six fertilization treatments of N0, N10, N20, N30, N40, N50 were designed. The cotton agronomic traits and yield and spatial and temporal variation of soil nitrate-N were studied in different growth and development stages of cotton. The results showed that: the number of bolls per plant and cotton production could be increased by using nitrogen. The yield would be increased with increasing amount of nitrogen, but there was a downward trend when the amount of nitrogen was more than a certain range. The content of nitrate nitrogen could be significantly improved by using nitrogen fertilizer in soil. The application amount of nitrogen of 450 kg/hm² could not only reduce the residual nitrate-N in soil but also stabilize the yield. But the excess application of nitrogen would cause the accumulation of nutrients and their leaching downward. There was nutrient competition of the roots in red date and cotton intercropping system. There was strong nitrogen competition in the region that was 50 to 100cm from the red date trees, the nitrogen competition increased after flowering stage, and achieved the maximum in the boll period, but the nitrogen competition would be weakened with the distance increase between the red date trees.