In this article, we have proposed a simple, environmentally benign and highly effective method for the reduction of graphene oxide (GO) by using carbonic acid as a chemical reducing agent to synthesize the reduced graphene oxide (rGO). Carbonic acid has been synthesized by mixing the dry ice (solid CO₂) with deionized water and by the mixing of acetic acid and sodium bicarbonate. The formed carbonic acid utilized to remove the oxygen‐containing functionalities of GO to produce rGO. Surprisingly, the synthesized rGO has shown aqueous dispersible property, which helps to disperse rGO in water for a prolonged time. The electrochemical activity of resulting materials has been achieved by measuring specific capacitance by cyclic voltammetry (CV) and galvanostatic charge‐discharge (GCD). Specific capacitance of resultant material is 350.3 F g⁻¹ at 1 A g⁻¹ with good cyclic stability performance indicating supercapacitive nature of the resultant material. According to the data obtained, it is observed that as‐prepared carbonic acid is capable of producing carboxyl functionalized graphene which leads to disperse rGO in water. This preparative method will overcome the problems to prepare rGO dispersion in aqueous medium rather than in hazardous organic solvents.