This study describes the preparation and application of a titanium dioxide modified carbon paste electrode for ascorbic acid determination in orange fruit samples by square wave voltammetric method. While the electrochemical behavior of ascorbic acid was investigated using cyclic voltammetry, square wave voltammetry was used for determination of ascorbic acid in orange samples collected from selected localities of Ethiopia. Compared to the unmodified carbon paste electrode, ascorbic acid showed oxidative peak with an enhanced peak current illustrating the catalytic activity of titanium modified carbon paste electrode towards its oxidation. Under optimized solution pH and square wave voltammetric parameters, the oxidative peak current showed linear dependence on the concentration of ascorbic acid in the range 0.3125 to 20 mM with correlation coefficient (R 2 ) of 0.9981. In this study, ascorbic acid content of freshly orange fruit samples in Asayta local market collected from Metehara, Tisabalima, Saynt and Mekoy were determined and compared by square wave voltammetric using Titanium dioxide modified carbon paste working electrode. The Vitamin C content of the studied orange fruits from Metehara, Tisabalima, Saynt and Mekoy was 68.90, 60.22, 59.90, 33.34 mg/100 mL, respectively indicating that its content in the sample from Metehara orange being the highest. Recovery result of 97.8% validated the applicability of the method for the determination of vitamin C in real samples. Keywords: Ascorbic Acid, Carbon Paste Electrode, Titanium Dioxide, Square Wave Voltammetry, Fresh Orange Fruit.