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The costs of drip irrigation installations can be reduced if the systems are designed using a lower uniformity. However, it remains unclear whether a lower system uniformity will result in a decreased crop yield and product quality in arid regions. Field experiments were conducted in arid environments in the 2010 and 2011 growing seasons of cotton to evaluate the effects of system uniformity on plant growth, nitrogen uptake, and lint yield and quality. In the experiments, three Christiansen uniformity coefficients (CU) of approximately 65%, 80%, and 95% (referred to as C1, C2, and C3, respectively) and three irrigation levels of 50%, 75%, and 100% of full irrigation were used. During both seasons, a great decrease in the CU for plant height and leaf area index (LAI) was observed for the low and medium uniformity treatments of C1 and C2, while a slight increase in the CU was observed for the high uniformity treatment of C3. System uniformity imposed an insignificant influence on the mean values of plant height, LAI, nitrogen uptake, and quality parameters, but a lower system uniformity significantly reduced the CU for plant height, LAI, nitrogen uptake, and lint yield. The influence of system uniformity on lint yield was related to the deficit level of irrigation and the degree of satisfaction of weather conditions for obtaining the potential yield. When the weather condition (e.g., temperature) is not a limiting factor for crop growth, increasing system uniformity resulted in a significantly greater lint yield. In arid regions, the use of a drip irrigation uniformity that is lower than the values recommended by the current standards should balance the installation and operation costs, crop production, and product quality.