Abstract: The luminol-functionalized gold nanoparticles (L-Au NPs) exhibited excellent electrochemiluminesent (ECL) performance. In this work, a new ECL aptasensor for sensitive detection of cacinoembryonic antigen (CEA) was constructed with the L-Au NPs as base material and the aptamer with specific recognition as the recognizing element. The ECL aptasensor for CEA detection exhibitsed a linear range from 5.0×10^-10 to 5.0×10^-6 g/L and the detection limit was 1.8×10^-10 g/L (R_SN=3). Moreover, the proposed method was applied to determine the CEA in human serum samples with the recovery of 85.3%~113.6%, and the relative error was less than 2.9% compared with the enzyme-linked immunoassay method. The studies supplied a general methodology to enhance ECL efficiency and showed a promising application prospects in the field of biological detection.