Superoxide ion was generated by the electrochemical reduction of oxygen at a platinum electrode in dimethylsulphoxide (DMSO). This work was focused on the nucleophilicity and scavenge of electrogenerated|superoxide ion by cyclic voltammetry. The nucleophilic displacement reactions of superoxide ion with ethyl acetate and diethyl adipate were discussed and the reason for remarkable influence of diethyl adipate was elucidated. The scavenging activity of ascorbic acid was evaluated and the result allowed the conclusion that the scavenging ability of ascorbic acid is much lower in DMSO than in aqueous phase. UV|spectrum of electrogenerated superoxide ion in DMSO exhibited a single absorption band with λ max at 275 nm, which certified further that the method of electrogeneration was reliable and superoxide ion was stable in DMSO. Superoxide ion was generated by the electrochemical reduction of oxygen at a platinum electrode in dimethylsulphoxide (DMSO). This work was focused on the nucleophilicity and scavenge of electrogenerated | superoxide ion by cyclic voltammetry. The nucleophilic displacement reactions of superoxide ion with ethyl acetate and diethyl adipate were discussed and the reason for remarkable influence of diethyl adipate was elucidated. The scavenging activity of ascorbic acid was evaluated and the result allowed the conclusion that the scavenging ability of ascorbic acid is much lower than DMSO than in aqueous phase. | spectrum of electrogenerated superoxide ion in DMSO exhibited a single absorption band with λ max at 275 nm, which certified further that the method of electrogeneration was reliable and superoxide ion was stable in DMSO.