In this study, a novel and effective electrochemical sensor for determination of dopamine (DA) was successfully developed by the modification of a glassy carbon electrode (GCE) using Pd nanoparticles deposited on (3-aminopropyl)triethoxysilane functionalized nanoceria (Pd@CeO2-APTES) and nation used as a protective membrane. The synthesized nanocomposites were evaluated using X-ray diffraction, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy. Moreover, the electrochemical properties of the modified electrodes were investigated using cyclic voltammetry, electrochemical impedance voltammetry, and differential pulse voltammetry (DPV) The Nf/Pd@CeO2-APTES/GCE showed a linear range of 2.5-149.5 mu M for DA by DPV with a notable sensitivity of 3.89 mA mM(-1) cm(-2) and a low limit of detection of 0.46 mu M based on the signal-to-noise ratio of 3 (S/N = 3). In addition, the sensor exhibited satisfactory selectivity, remarkable sensitivity, repeatability, and reproducibility. The sensor protected 92.07% of its initial electrocatalytic activity toward the oxidation of dopamine after 30 days. The Nf/Pd@CeO2-APTES/GCE was used for determination of DA in serum samples. The results indicate that the sensor can be a notable device for the detection of DA in biological fluids.