Congestive heart failure (CHF) is a major cause of hospitalizations, morbidity, and mortality in Western societies. In addition to optimal medical and device therapy, exercise training is an important adjunct treatment option for CHF patients. MicroRNAs (miRNAs, miRs) participate in a variety of physiological and pathological processes. Dynamic regulation of circulating miRNAs during exercise in healthy persons and athletes has recently been documented, however, the response of circulating miRNAs to exercise in CHF patients is undetermined. Twenty-eight CHF patients underwent a symptom-limited incremental cardiopulmonary exercise test on a bicycle ergometer using a standardized exercise protocol of revised Ramp10 programs at Shanghai Tongji Hospital. Blood samples were collected before and immediately after an acute exercise session. RNA was extracted from the serum and selected miRNAs were determined using quantitative polymerase chain reactions. Moreover, inflammatory and muscle damage markers were determined by enzyme linked immunosorbent assays. We found that serum miR-21, miR-378 and miR-940 levels were significantly up-regulated immediately following an acute exercise while the rest were not changed. In addition, no robust correlation was identified between changes of these miRNAs and exercise capacity, muscle damage or inflammation. In conclusion, serum miR-21, miR-378, and miR-940 increase in response to an acute exhaustive exercise in CHF patients. Further studies are needed to clarify the potential use of circulating miRNAs as biomarkers of exercise adaptation in CHF patients, and if they have any use as prognostic markers of cardiovascular outcomes.