Straw return is a low-cost, nature-based practice to enhance soil carbon sequestration, stabilize crop yield, and support sustainable agriculture. Its long-term effectiveness, however, depends on coordinated carbon-nitrogen management, particularly in nutrient- and temperature-limited dryland systems. To address this challenge, a four-year field experiment was conducted in a dryland maize system, in which three straw-return rates-full (S1, 100% of harvested straw returned), moderate (S2, 60% returned), and low (S3, 20% returned)-were combined with three nitrogen rates (N1: 225, N2: 180, and N3: 135 kg N ha-1 ). Crop yield, soil carbon dynamics, life-cycle carbon footprint (CF), and economic-ecological performance were systematically evaluated. Over the four-year period, moderate straw return (60% of harvested straw returned) combined with 225 kg N ha-1 achieved the best overall trade-off, increasing aboveground biomass by 4.9-8.7% and grain yield by 2.9-6.2%, reducing soil CO 2 emissions by 4.0-8.0%, increasing soil organic carbon by 0.8-1.4%, and improving economic returns by 14.0-18.8% compared with full straw return. Although 20-40% reductions in nitrogen input decreased soil carbon losses and carbon footprint, they caused significant yield penalties, ultimately weakening overall economic-environmental performance. Within the assessed life-cycle boundary, all treatments were estimated to remain net greenhouse gas sources; however, 60% straw return consistently exhibited the lowest annual carbon footprint (569-1994 kg CO 2 -eq ha-1 yr-1 ), consistent with greater SOC storage. Full straw return produced the highest net ecosystem carbon balance but did not increase SOC, indicating enhanced losses of non-stabilized carbon. Using an AHP-entropy weighted TOPSIS evaluation, 60% straw return with 225 kg N ha-1 emerged as the optimal strategy for balancing productivity, environmental performance, and economic returns. These results show that coordinated straw-N management can enhance soil carbon efficiency and economic returns while reducing environmental costs, providing a practical and scalable pathway toward low-carbon maize production in the Loess Plateau and other temperate, semi-arid, rainfed drylands.