Objective Congestive heart failure (CHF) is the final common pathway of various heart diseases. Calcineurin, a calcium/calmodulindependent phosphatase consisting of a catalytic subunit A (CnA) and a regulatory calcium-binding subunit B (CnB), is activated in heart failure. This study aimed to investigate the relationship between mRNA level of calcineurin in circulating T-lymphocyte and that in myocardium in patients with CHF. Methods A total of 38 patients with CHF (aged from 29 to 62 years) were included in this study. The mRNA levels of alpha- and beta-isoform of CnA in left ventricular anterior papillary muscle and peripheral lymphocytes were determined by semi-quantitative reverse transcription polymerase chain reaction. Pearson linear correlation analysis was performed, and difference was considered statistically significant at a P value <0.05. Results Calcineurin mRNA levels in lymphocytes were positively correlated with those in myocardium (for CnA-alpha mRNA, r=0.820; for CnA-beta mRNA, r=0.875; both P<0.01). CnA-beta mRNA levels in both circulating lymphocytes and myocardium increased significantly with increasing NYHA class (r=0.877 for peripheral blood and r=0.805 for cardiac muscle; both P<0.01). Conclusions The mRNA level of CnA-beta in circulating lymphocytes is positively correlated with that in myocardium and is a promising marker for the severity of cardiac dysfunction in patients with CHF.