The aim of this study was to explore the impact of ankylosing spondylitis (AS) and the disease-related variables, psychological status and the quality of life on the female patients' sexual function measured according to the Female Sexual Function Index (FSFI). Thirty-seven sexually active female AS patients and 33 healthy controls were enroled in this study. Their demographic data were evaluated and the generalised pain in patients with AS was assessed according to the visual analogue scale (0-100 mm). Laboratory tests were conducted in order to measure the C-reactive protein (CRP) and erythrocyte sedimentation rates (ESR) of the patients. In comparison to the healthy control group, patients with AS had significantly lower scores in each of the five domains of the FSFI except for the pain domain (P<0.05). The disease activity, functional status, quality of life, radiological score and CRP levels were negatively correlated with the FSFI (P<0.05). No significant correlation was observed with the disease duration, smoking status, depression, anxiety, pain and ESR when the total scores and the scores from the domains of the FSFI were compared. The sexual function is impaired in female patients with AS. This impairment in the sexual function is especially related to the functional status and disease activity among the clinical and laboratory parameters.