A highly selective electrochemical method was developed for the simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA) using a glassy carbon electrode modified by radio frequency nitrogen/ argon plasma (N₂/Ar) mediated graphene sheets / graphene ribbons (GS/GR).The performance of the electrode towards was investigated by cyclic voltammetry, different pulse voltammetry (DPV) and chronoamperometry. The excellent electrocatalytic activity toward the oxidation of AA, DA and UA was demonstrated with a well-separated voltammetric peaks between AA/DA, DA/UA and AA/UA are 220,150 and 372 mV (vs. Ag/AgCl) in DPV, respectively. The detection limits (S/N = 3) of 0.00053 µM, 0.00025 µM, 0.00057µM were obtained for AA, DA and UA in PBS, respectively. Due to the synergistic effect between the high conductivity of graphene hybrid and the catalytic activity of N₂, the as-prepared composite showed excellent performance. Additionally, the N₂/Ar/GS/GR/GCE electrode presented well anti-interference ability, stability and reproducibility.