Based on the catalytic oxidation effect of nickel-manganese oxide complex against corbic acid, an electrochemical sensor for rapid detection of ascorbic acid was constructed by modifying glassy carbon electrode with nickel-manganese oxide complex. Ni - Mn - based oxide composites were prepared by one - step hydrothermal method. Electron microscopy (SEM), EDS, X-ray diffraction (XRD) and Fourier infrared spectroscopy (FT-IR) were used to characterize the morphology, elemental composition ratio and structure of the materials.The structure shows that the material is a spherical structure with voids on the surface. All the diffraction peaks can be indexed as Mn2O3(JCPDS No. 41-1442) ,NiMnO3 (JCPDS No. 48-1330) , and Mn-O and NI-O functional groups exist. According to the response of electric signal, the sensitive and rapid detection of anticorbic acid is realized. The composite material was modified on the electrode surface by drip coating method. The electrochemical behavior of ascorbic acid on the nickel-manganese oxide composite electrode was measured by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Finally, the drop coating amount was determined to be 10μL under the condition of acetic acid buffer solution pH=4. The peak oxidation current of ascorbic acid has a linear relationship with the concentration from 0.4 to 7600 μmol/L. The linear equation is Ip= 0.0039x (mmol/L)+11.643, and the detection limit is 0.023 μmol/L. The sensor has been applied to the determination of ascorbic acid in fruit drinks. The recovery rate of the sensor is 95.5% ~ 103.12%, indicating that it has a good application prospect in food analysis and biochemical analysis.