A set of unique triptycene-based and organic Schiff-base-linked polymers (TBOSBLs) are conveniently synthesized in which triptycene motifs are connected with 1,3,5-triformylphloroglucinol units via Schiff-base linkages. TBOSBLs are amorphous, thermally stable with a reasonable surface area (SABET up to 649 m2/g), and have abundant nanopores (pore size < 100 nm). TBOSBLs are good sorbents for small gas molecules (such as CO2, H2, and N2) and they can selectively capture CO2 over N2. Additionally, TBOSBLs show superior antiproliferative activity against human colorectal cancer cells relative to previously reported covalent organic frameworks (COFs). The mechanism of cell death is also studied elaborately. Copyright © 2020 American Chemical Society.