MicroRNAs (miRs) have emerged as promising biomarkers for diagnosing and predicting the prognosis of liver injury. This study aimed to compare the performance of two Luminex platforms, MAGPIX and FLEXMAP 3D, utilizing the innovative Dynamic Chemical Labelling (DCL) technology for direct detection and analysis of miR-122-5p in serum samples from patients with liver injury. Serum samples were collected from four patients with liver injury and four healthy controls. The levels of miR-122-5p were measured using the DCL method on both MAGPIX and FLEXMAP 3D platforms. The performance evaluation included the limit of detection (LOD), intra-assay and inter-assay precision, as well as accuracy. The results demonstrated that both platforms exhibited high sensitivity and specificity in detecting miR-122-5p in serum samples from patients with liver injury. However, FLEXMAP 3D indicated a lower LOD compared to MAGPIX. The precision of miR-122-5p detection was similar between the two platforms. In conclusion, both MAGPIX and FLEXMAP 3D Luminex platforms, in conjunction with DCL reagents, proved to be reliable and sensitive tools for detecting miR-122-5p in serum samples from patients with liver injury. Although both platforms were effective, FLEXMAP 3D exhibited slightly better performance, suggesting its preference for miR detection in clinical settings. These findings offer valuable insights for selecting the appropriate Luminex platform for miR detection in patients with liver injury and beyond.