Abstract Objectives We aimed to assess the growth arrest specific protein 6 (Gas6) and soluble Axl (sAxl) levels in the familial Mediterranean fever (FMF) patients, and to investigate the correlation between the levels of these with the inflammatory markers including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and fibrinogen. Materials and methods Seventy nine FMF patients (35 in attack period and 44 in attack-free period) and 40 healthy controls were involved in the study. The levels of serum Gas6 and sAxl were measured by enzyme-linked immunosorbent assay (ELISA) method. Results Gas6 levels of the FMF patients with attack were significantly lower than both the attack-free patients and the healthy controls (p=0.007 and p=0.003, respectively). However, no significant difference was detected between the Gas6 levels of the attack-free patients and the healthy controls (p>0.05). sAxl levels of the FMF patients with attack were significantly lower than the healthy control (p=0.007). A positive correlation was found between the Gas6 and CRP levels of the FMF patients with attack (r=0.379, p=0.025). Conclusions This study indicates that decreased serum Gas6 and sAxl levels may be associated with FMF attack period. Further studies on the role of the Gas6/Axl system in FMF are needed.