Meta-surface plasmon resonance (MetaSPR) chip and gold nanoparticles (AuNPs) were employed to construct an immunocompetitive sensing platform for detecting chloramphenicol (CAP) in aquatic products. The structure, particle size and other properties of the chip and AuNPs were characterized using scanning electron microscopy (SEM) and a nanoparticle size analyzer. Binding affinities in varying conditions were tested to verify the feasibility of the immunocompetitive sensing strategy. Under optimized conditions, the detection limit of the sensor was 0.06 ng/mL, with a linear detection range of 0.125-16 ng/mL (R² = 0.998). The spiked recovery rates of CAP in aquatic products ranged from 102.5% to 105.0%, indicating excellent stability and specificity. Furthermore, the sensor was rapid (10 min) and high-throughput (simultaneous detection in 96 wells), demonstrating significant potential in food safety monitoring.