Microfluidic technologies represent a new platform for investigating chronic kidney disease and renal fibrosis, which remain global health problems with limited opportunities for early diagnosis. These systems enable accurate modeling of renal microenvironments and simulation of critical pathophysiological processes such as proteinuria and immune cell-mediated inflammation, achieving better resolution than traditional 2D cultures or animal models. Microfluidic biosensors enable non-invasive and highly sensitive detection of kidney disease biomarkers such as albumin and neutrophil gelatinase-associated lipocalin (NGAL), and wearable epidermal patches enable continuous monitoring of electrolytes and metabolites. In the field of therapeutics, microfluidic systems support high-throughput drug screening at physiologically relevant perfusion and improve drug targeting and bioavailability. Integration with artificial intelligence and multi-omics analysis refines data interpretation and discovery of new biomarkers. Despite significant progress, challenges remain in terms of scalability, reproducibility and regulatory approval that will need to be addressed through interdisciplinary collaboration.