Chemical activation of carbon materials is critical to modify their textural and surface properties in an effort to optimize their supercapacitive performance as electrode materials for supercapacitors. This present work investigates the effects of nitric acid activation on the textural, surface, and supercapacitive properties of ul-tra-small carbon nanospheres with a uniform size of 24 nm synthesized through a unique catalytic emulsion polymerization strategy. Nitric acid activation has been undertaken at different temperatures for various time. The effects of these two activation parameters have been systematically examined, with some important cor-relations established. The optimum activation conditions for achieving the best supercapacitive performance in different aqueous electrolytes have been identified.