Microporous, hypercrosslinked poly-p-phenylenes with surface area of up to 1735 m2 g−1 have been prepared by combination of super acid catalyzed polymerization and the double aromatic nucleophilic substitution reaction. The surface area and pore size can be controlled by varying the amount of the crosslinking reagents, which tuned the crosslinking degree effectively. The capacity of adsorption of CO2 of the MPNs largely depends on their specific surface areas.