Main observation and conclusionBy a strategy of fine‐tuning of packing mode between the adjacent layers in a 2D net metal‐organic frameworks (MOFs) through ligand changing, two 2D sql‐type MOFs with highly selective CO2 uptake, CuHIN and CuHPB, were successfully synthesized. Compared with the precursor MOF‐2, the fine‐tuning structure of CuHIN shows selective adsorption of CO2 over N2 and CH4 with the CO2 uptake amounts as high as 4.7 wt% at 0.15 bar and at 298 K, and CO2 selectivity towards N2 and CH4 is 165.8 and 10.22 at 1 bar and at 298 K, respectively. In addition, for the 2D MOFs, the dynamic porous structure depends on the interaction of the adjacent layers. The suitable interaction is good for gliding smoothly and gas adsorption.