Background: Sarcopenia is highly prevalent in heart failure (HF) patients, and the involvement of biomarkers in its pathophysiology is suggested, but little has been studied concerning HF sarcopenic patients. Objectives: To evaluate the association between inflammatory and humoral markers with sarcopenia, as well as the impact of sarcopenia on quality of life and functional capacity in older HF patients. Methods: In this cross-sectional study, 90 outpatient HF patients, aged & GE; 60 years, were evaluated for sarcopenia (EWGSOP2 diagnostic criteria), inflammation (high-sensitive C-reactive protein [hs-CRP], Interleukin-6 [IL-6], tumor necrosis factor alpha [TNF-& alpha;]) and humoral markers (total testosterone and insulin-like growth factor-1 [IGF-1]), physical activity (International Physical Activity Questionnaire), quality of life (Minnesota Living with Heart Failure Questionnaire), and functional capacity (6-minute walk test). The adopted level of significance was p<0.05. Results: Patients had a mean age of 69.4 & PLUSMN; 7.2 years, 67.8% were male, with left ventricular ejection fraction (LVEF) of 35.9 & PLUSMN; 11.9% and 22 (24.4%) were sarcopenic. Age (73.1 & PLUSMN; 8.1 and 68.3 & PLUSMN; 6.5 years; p= 0.006), body mass index (BMI) (23.1 & PLUSMN; 2.8 and 28.2 & PLUSMN; 4.2 kg/m2; p <0.001), and LVEF (29.9 & PLUSMN; 8.8 and 37.9 & PLUSMN; 12.1%; p= 0.005) were different between groups with and without sarcopenia, respectively. After adjusting for age, ethnicity, BMI, LVEF, and the use of angiotensin converting enzyme inhibitors/angiotensin receptor blockers, sarcopenia was associated with higher serum levels of IL-6 and worse functional capacity. Conclusion: In HF patients, sarcopenia was associated with IL-6 levels and functional capacity.