In the present study, a carbon screen-printed disposable microchip as a microstructured two-electrode system was developed for the establishment of a ferricyanide chronoamperometric total antioxidant capacity (FC-TAC) assay for vegetables. Ferricyanide cyclic voltammetry (FCV) measurements were also performed using the microchip to define optimum conditions for the FC-TAC assay. As antioxidants, we chose ascorbic acid (vitamin C), chlorogenic acid, and α-tocopherol (vitamin E). The electrochemical response to an antioxidant was indirectly determined through ferricyanide and was strongly affected by the solubility of both the mediator and the antioxidant in the measurement solution. By intensive investigation, it was found that 80% (v/v) methanol was the best solvent for the FC measurements and vegetable extraction. Under optimum conditions for the FC-TAC assay, micro-volume measurement of 30 µL without reaction time was realized using the microchip, and calibration curves for three antioxidants were successfully obtained with excellent determination coefficients (r2 > 0.986, n = 5). Finally, the conventional DPPH test using ten vegetable extractions was applied for comparison with the present FC-TAC method, and the results obtained showed good correspondence (r2 > 0.928, n = 5).