BACKGROUND: Coronary artery disease (CAD) is a current major public health concern. Immunity and inflammation are involved in all phases of CAD and there is a dynamic balance between cells and molecules. Interleukin 17A (IL17A) concentrations are higher in male patients with acute myocardial infarction than in women. In this study, we evaluated if the IL17A concentrations in male CAD patients (MPs) differed from those in female patients (FPs) and male controls (MCs). Moreover, FPs were compared with female controls (FCs). METHODS: This was a cross-sectional, prospective, and analytical study conducted between March 2012 and August 2013 that enrolled 40 patients (24 men and 16 women) with stable CAD and 20 healthy volunteers (12 men and 8 women) were selected as controls and were matched with the patients (1:2) for sex and age (± 3 years). Comparative analyses of IL17A concentrations in serum and cell culture with and without stimulation were performed between MPs and MCs, MPs and FPs, and FPs and FCs. The lower detection limit was 3.91 pg/mL. RESULTS: The comparison of the IL17A concentrations showed: after 48 hours of cell culture with stimulus: MP = 451.67 (99.02 - 892.58) vs. MC = 135 (3.91 - 285), P = 0.04; after 48 hours of cell culture with stimulus: MP = 451.67 (99.02 - 892.58) vs. FP = 131.21 (3.91 - 231.97), P = 0.02; after 48 hours of cell culture with stimulus: FP = 131.21 (3.91 - 231.97) vs. FC = 173.78 (3.91 - 642), P = 0.24. CONCLUSION: This study revealed higher IL17A concentrations in the stimulated cells isolated from the MPs than in those isolated from FPs and MCs. These findings support the hypothesis that when exposed to certain stimuli, cells isolated from MPs with chronic CAD may produce higher IL17A concentrations than those from FPs and MCs.