Polycrystalline fibers of porous coordination polymers (PCPs) were synthesized from free-standing alumina nanofiber materials by a coordination replication process. The diameter and morphology of fibrous PCP architectures were controlled by the concentration of aluminum salts and the pH of the reaction solution of replication, respectively. CO2 adsorption measurement proved the presence of hierarchical porosity composed of both micropores and mesopores in PCP fibers.