在城市发展转向存量提质阶段的背景下，优化“三生”空间规模结构成为高质量发展的核心命题。构建“生态规模约束—功能比例适配—内部结构协同”的理论分析框架，基于多源数据揭示中国城市空间结构的深层矛盾。研究表明，当前，中国城市“三生”空间的主要矛盾已从总量规模短缺转向结构性比例失调，生态空间虽守住规模管控底线，但整体质量仍然偏低，建设空间在宏观层面表现为保障支撑比例失衡与产居结构分化、在微观层面陷入内部结构扭曲与服务供需脱节的困境。据此提出“锁定规模边界—纠偏宏观比例—重构内部结构”的递进式优化范式，并从精准治理视角指出，应加快关键结构指标的关系研究，构建标准制定与量化支撑体系，从而为推动城市空间治理从经验判断向精准量化转型提供科学依据。

As urban development shifts to the stage of stock improvement and quality enhancement， optimizing the scale structure of “production-living-ecological” space has become a core issue for high-quality development. This study constructs a theoretical analytical framework of “ecological scale constraint - functional proportional adaptation - internal structure coordination” and reveals the underlying contradictions in China’s urban spatial structure based on multi-source spatial data. The results show that the main contradiction of “production-living-ecological” space in Chinese cities has shifted comprehensively from total scale shortage to structural proportional imbalance. Although ecological space maintains the bottom line of scale control， its overall quality remains low. At the macro level， construction space exhibits imbalanced supporting space and a differentiated production-residence structure； at the micro level， it falls into internal structural mismatch and a disconnection between service supply and demand at the micro level. Accordingly， a progressive optimization paradigm of “locking scale boundaries - correcting macro proportions - restructuring internal structure” is proposed. Furthermore， from the perspective of precise governance， it is suggested to accelerate the standard transformation of key structural indicators and the construction of a quantitative support foundation， so as to provide a scientific basis for promoting the transformation of spatial governance from empirical judgment to precise quantification.