AbstractOrganic supercapacitors have attracted interest as promising “green” and efficient components in energy storage applications. A polydiacetylene derivative coupled with reduced graphene oxide was employed, for the first time, to generate an organic pseudocapacitance‐based supercapacitor that exhibited excellent electrochemical properties. Specifically, diacetylene monomers were functionalized with perylenediimide (PDI), spontaneously forming elongated microfibers. Following polymerization through UV irradiation, the PDI–polydiacetylene microfibers were interspersed with reduced graphene oxide (rGO), generating a porous electrode material exhibiting a high surface area and facilitating efficient ion diffusion, both essential preconditions for supercapacitor applications. We show that PDI–polydiacetylene has an important role in enhancing the electrochemical properties as a supercapacitor electrode. Besides stabilizing the microporous electrode organization, the delocalized π electrons in both the PDI residues and conjugated network of the polydiacetylene contributed to a significantly higher capacitance (specific capacitance >600 F g−1 at 1 A g−1 current density), longer discharge time, and high power density. The PDI–polydiacetylene‐rGO electrodes were employed in a functional supercapacitor device.