Nitrogen‐linked hexaazatrinaphthylene polymer (N2‐HATN) as organic cathode material with low HOMO–LOMO gap was synthesized and was observed to possess reversible high capacity and unexpected long‐term cycling stability. The pre‐treated N2‐HATN and pRGO combination demonstrated good structure compatibility and the resultant cathode exhibited a constant increment of capacity during the redox cycles. The initial capacity at 0.05 A g−1 was 406 mA h−1 g−1, and increased to 630 mA h−1 g−1 after 70 cycles. At 0.5 A g−1 discharging rate, the capacity increased from an initial value of 186 mA h−1 g−1 to 588 mA h−1 g−1 after 1600 cycles. The pseudocapacitance‐type behavior is postulated to be attributed to the structure compatibility between the active material and pRGO.