Electrochemiluminescence (ECL) is a widely applied technique for trace detection and analysis, but the stability of luminophores and external environmental factors strongly influence the analysis results. Herein, a low-potential ECL sensing platform based on enhanced nanomaterial catalysis for the traditional system luminol-H2O2 is proposed for the detection of neuron specific enolase (NSE). In this strategy, Au nanoparticles modified with three-dimensional graphitic phase carbon nitride (3DCNA) were used as a solid platform for antibodies (Ab2), which not only solved the problem of accumulation between traditional two-dimensional nanosheets but also had good biocompatibility, ensuring the accuracy of the analysis results. CoSn(OH)6, benefiting from its inherently higher catalytic activity and greater number of adsorption sites on perovskite hydroxide, can catalyze the oxidationreduction reaction of H2O2 to improve the ECL behavior of luminol and lower the applied voltage to reduce damage to biological activity. Owing to these exceptional properties, this proposed sandwich ECL immunosensor was explored for the primary diagnosis of SCLC by detecting NSE with a detection limit of 0.18 pg mL–1. It exhibited satisfactory linearity in the range of 0.0005 ng mL–1 to 100 ng mL–1 with favorable stability, excellent specificity, and good reproducibility. This study provides an important reference for low-potential ECL with promising application prospects in actual clinical analysis and detection.