Abstract: Plasma renin concentration (PRC) measurement, owing to its ease of operation, high degree of automation, and favorable stability, is gradually replacing plasma renin activity (PRA) as a diagnostic indicator for screening and diagnosing primary aldosteronism (PA) that possesses both operational advantages and potential for widespread adoption. However, its clinical application still requires prudent evaluation. The core challenge lies in the fact that PRC reflects the mass concentration of renin, which is not equivalent to the functional activity reflected by PRA. This discrepancy is particularly prone to misinterpretation in conditions with elevated prorenin levels, such as diabetic nephropathy, pregnancy, and reninoma. Furthermore, the lack of a standardized assay procedure and diagnostic cutoff values limits its homogeneous application across different settings. This article systematically reviews the current status of PRC in the diagnosis of PA, analyzing its advantages and limitations compared to PRA from the perspectives of measurement principles, analytical performance, clinical efficacy, and guideline recommendations.