An electrochemical sensor based on a screen-printed electrode modified with a SiC/CDC-CS composite was developed for the sensitive and rapid determination of methyl parathion. The composite was prepared using a solution-assisted dispersion method and deposited onto the SPE working surface by drop casting. Material morphology was investigated by scanning electron microscopy, while the electrochemical properties of the electrodes were evaluated using cyclic voltammetry and electrochemical impedance spectroscopy. SEM images confirmed the distribution of small CDC particles over spherical SiC particles and the formation of a heterogeneous composite structure. Compared with the bare SPE, the SiC/CDC-CS/SPE exhibited higher redox currents and lower charge-transfer resistance. Methyl parathion was quantified using square-wave voltammetry. Chitosan had no substantial influence on the analytical signal and primarily acted as a film-forming binder that stabilized the nanomaterials on the electrode surface. The maximum electrochemical response was obtained at pH 6.0 with an accumulation time of 6 min. The sensor provided a linear concentration range of 1×10^-9~1×10^-5 g/mL and a detection limit of 5×10^-9 g/mL. The electrode process was characterized as an adsorption-controlled, proton-coupled electron-transfer reaction. The sensor demonstrated good selectivity and stability and was successfully applied to real water samples, providing recoveries of 100.42-103.30%. These results highlight the potential of the SiC/CDC-CS/SPE platform for environmental monitoring.