Adsorptive separation technology is gradually replacing traditional gas purification methods due to its high separation efficiency and mild operating conditions. Metal-organic cages (MOCs), featuring tunable pore structures and diverse topological configurations, have emerged as advantageous adsorbent materials, showing excellent application prospects in the separation of C?H?/CO?. In this study, we designed a ZrT-1-OMe metal-organic cage based on the functionalized ligand 2-methoxyterephthalic acid (BDC-OMe), achieving controllable regulation of the pore microenvironment while maintaining the stability of the parent framework. The methoxy-functionalized ZrT-1-OMe exhibits stronger affinity and selectivity for acetylene, with an adsorption capacity of 58.2 cm3/g, a C?H?/CO? (v:v = 50/50) selectivity of 3.92, and a dynamic separation duration of 13 min/g.