<p> A&#xa0;simple and rapid electrochemical method based on a composite of cadmium telluride quantum dots (CdTe QDs) and MXene is developed for the simultaneous determination of rutin and quercetin in food samples. The CdTe QD-MXene composite is synthesized via the in situ growth of CdTe QDs on MXene, which serves as a carrier and enhances electrical conductivity. Incorporating CdTe QDs into MXene interlayers effectively prevents agglomeration in MXene and provides more active sites for electrochemical determination. The developed electrochemical method can successfully determine rutin and quercetin, both individually and simultaneously, in aqueous solutions while achieving high stability and selectivity. Notably, the prepared sensor exhibits limits of detection of 3.300 × 10⁻⁸ and 3.268 × 10⁻⁷&#xa0;M for the simultaneous determination of rutin and quercetin, respectively. Moreover, the sensing platform is used for the determination of rutin in buckwheat, locust rice, and apples, with results well comparable to&#xa0;those obtained using ultraviolet spectroscopy. Finally, the proposed sensor is employed to monitor the hydrolysis of rutin into quercetin in buckwheat using an electrochemical method for the first time. This study provides new ideas for the application of electrochemical sensors in food and drug science.</p> Graphical Abstract <p></p>