A series of crosslinked porphyrin-based polyimides (PPBPI-CRs) were synthesized from 5,10,15,20-tetra[4-[(3-aminophenyl)ethynyl]phenyl]porphyrin (TAPEPP) and several dianhydrides via polymerization and crosslinking reactions. PPBPI-CRs exhibited excellently thermal and chemical stabilities. Meanwhile, PPBPI-CRs revealed decreased Brunauer-Emmett-Teller (BET) surface areas (628 - 115 m2 g-1) and enlarged pore sizes with increased conjugate and molecular sizes of dianhydrides. Moreover, PPBPI-CRs had carbon dioxide uptakes (0.67 -

2.33 mmol g-1 at 273 K and 1 bar) and CO2 isosteric enthalpies of adsorption (19.7 - 29.6 kJ mol-1) as well as CO2/N2 selectivities (42.5, 32.21, 36.91 and 74.65).