Crude oil capacity construction is a critical component of oilfield production and an essential part of oilfield production tasks. The effectiveness of capacity construction not only directly impacts annual production and benefits but also significantly influences the sustainable and stable development of the oilfield. Conducting phased quantitative evaluations of capacity construction effects and benefits is crucial for guiding the optimization of capacity construction structures in subsequent years. Currently, the internal rate of return (IRR) is the primary indicator used to assess benefits, while initial production performance is evaluated. However, this approach suffers from a lack of comprehensiveness, as it fails to quantitatively reflect other critical factors affecting production. To address this, this study proposes a comprehensive evaluation method based on key indicators such as initial daily production, decline rate, and contribution rate. This method aims to quantitatively analyze capacity construction effects, benefits, and overall production performance from multiple perspectives. Taking a typical oilfield (Oilfield A) as a case study, the annual capacity construction work is evaluated quantitatively, and optimization recommendations are provided to enhance capacity construction outcomes, offering practical insights for industry improvement.