Homopolymer PAN and triblock copolymer PAN-b-PMMA-b-PAN synthesized by RAFT polymerization were used to fabricate activated hierarchical porous carbon membranes by combining phase inversion, carbonization, and HNO3 activation method; during the preparation process, a lot of micro- and mesopores generated because of phase separation of PAN and microphase separation of PAN-b-PMMA-b-PAN.The hierarchical porous structure shortened ions transport paths and facilitated the rapid migration of electrolyte ions. When the polymer membrane was prepared by the casting solution with 5 wt% of PANb-PMMA-b-PAN and the electrochemical performance was tested at the current densities from 0.5 to 5 A g1, a high-end specific capacitance of 297.0 F g1 and a capacitance retention of 75% were obtained in three-electrode configuration; this specific capacitance remained above 90% of initial value after 2000cycles at 2 A g1 in 6 M KOH aqueous solution. Moreover, symmetric supercapacitors assembled with the prepared materials achieved high energy density (15.8 Wh Kg1) and power density (4000 W Kg1) in 1 M Na2SO4 solution. The unique features and structures endowed the electrode membrane with good capacitive performance in both three-electrode and two-electrode configuration, which can be used as electrode membranes for high-performance energy storage devices and other applications.