Abstract: A novel electrochemical sensor was constructed based on black phosphorus nanosheets/gold nanoparticles/silicon carbide nanocomposites (β-CD@BP/SiC/AuNPs). The black phosphorus nanosheets have excellent charge transfer ability, and the black phosphorus nanosheets/silicon carbide as conductive materials can enhance the electrochemical signal. Through the host-guest recognition effect of β-cyclodextrin on dopamine to form a complex, the adsorption of dopamine on the electrode surface is increased to generate an electrical signal. The content of dopamine in the unknown solution is detected by the change of the electrical signal. In this paper, transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and other methods were used to characterize the material synthesis of different modified electrodes, and the electrochemical reduction conditions and the experimental conditions for determining dopamine were further optimized. Under the optimal measurement conditions, the electrochemical measurement linear range was 5−20 μmol/L and 20−1000 μmol/L. The lowest detection limit (R_SN=3) was 0.55 μmol/L. This method was applied to the detection of actual blood, and the recovery rate of the standard addition was 93.35%−104.23%, with a relative standard deviation of 0.37%−7.37%, showing good recovery rate and accuracy. The above results indicate that this electrochemical sensor has potential application value in the detection of dopamine and is expected to sensitively detect the content of clenbuterol in food and dopamine in human serum.