UiO-66 in Zr-MOFs materials stands out in the research of supercapacitors due to its large specific surface, high stability and high heat resistance. In this paper, pure UiO-66 was successfully prepared using solvothermal method, and three PDA/UiO-66 composites with addition mass ratio of UiO-66 and dopamine of 2:1, 3:1 and 4:1 were prepared by autopolymerizing dopamine hydrochloride to form polydopamine at room temperature. The materials’ morphology and structure were examined using SEM, TEM and XRD, and the capacitive performances were analyzed by CV and GCD. The results indicated that the capacitor properties of UiO-66 could be improved to a certain extent with the appropriate amount of polydopamine coating. The PDA/UiO-66 composite with a mass ratio of 2:1 displayed a high specific capacitance of 822.04 F/g at 1 A/g, and maintained good capacity retention even after 4000 charge/discharge cycles in a three-electrode system. These results suggested that the PDA/UiO-66 composite had great potential as a supercapacitor electrode material.