The separation of ethylene (C2H4) and propylene (C3H6) is of great importance for their practical application.Hyper-crosslinked polymers (HCPs), which have the merits of abundant pore structures, exceptional stability, and the simplicity of synthesis, have the potential for the adsorptive separation C3H6/C2H4.Herein, two novel HCPs, namely NUT-17 and NUT-17-Me were synthesized based on indolo[3,2-b]carbazole-based monomers and rigid crosslinks.For the first time, these materials were applied to sep. C3H6/C2H4 mixturesNUT-17 and NUT-17-Me with abundant porous structure and exceptional thermal stability (470°C), can preferentially adsorb C3H6 rather than C2H4.In particular, the two HCPs reveal high C3H6/C2H4 (volume/volume 50/50) selectivity up to 9.3 for NUT-17 and 9.5 for NUT-17-Me under atm. conditions, which are higher than most reported high-performance C3H6-selective materials.D. functional theory (DFT) calculation results show stronger adsorption interactions for C3H6 compared to C2H4 in the optimized configurations of NUT-17 and NUT-17-Me.Furthermore, NUT-17 and NUT-17-Me demonstrate excellent repeatability, and their C3H6 storage capacities remain relatively stable after five cycles.Moreover, the dynamic breakthrough studies conducted at various C3H6 to C2H4 ratios demonstrate that both NUT-17 and NUT-17-Me exhibit high-efficiency separation capacities for C3H6/C2H4, indicating their promising potential for industrial adsorptive separation