Highly porous carbon material was prepared from defluorination of polytetrafluoroethylene (PTFE) with lithium metal, and its electric double layer capacitance was measured in 1.0 M H2SO4 aqueous electrolyte. The solid-solid reaction product of PTFE film with Li foil had micro/nano domain structure consisting of a one-dimensional carbon chain (carbynelike structure) and LiF. After cross-linking of the carbon chain and condensation of LiF in the reaction product, highly porous carbon containing micropore and meso/macropore was obtained by removal of fine LiF particles with dilute HCl solution. This porous carbon derived from PTFE and Li (PCPTFE) showed higher capacitance (Brunauer-Emmett-Teller, BET, surface area 1045 m(2) g(-1), capacitance 199 F g(-1)) than activated carbon fiber with almost the same BET surface area (1084 m(2) g(-1), 134 F g(-1)). The higher capacitance of PCPTFE can be related to the surface conditions, the matrix carbon structure, and, especially, the pore structure of PCPTFE.