Benign joint hypermobility syndrome (BJHS) is defined as the presence of musculoskeletal symptoms in persons with generalized joint laxity in the absence of systemic rheumatologic disease. There is an association between soft tissue rheumatism, entrapment neuropathies, and BJHS. The purpose of the study was to identify the relationship between BJHS and carpal tunnel syndrome (CTS). Ninety patients were included in the prospective controlled study. All selected participants were referred to our electrophysiological laboratory with clinical diagnosis of CTS. Subsequently, subjects were divided into two groups as group I and II. Group I included patients with CTS and group II had patients without CTS based on electrophysiological findings. All subjects were assessed for existing BJHS by using the Brighton 1998 criteria. Fifty-five patients were recruited into group I (CTS) and 35 subjects were in group II. The mean age in group I and II was 49.5+/-10.8 and 40+/-9.9 years, respectively. The subjects in group II were younger than those in group I (p<0.05). The mean Beighton score was 2.04+/-2.7 and 1+/-1.68 in groups I and II, respectively. In patients with CTS, BJHS rate was markedly higher than those in patients without CTS with respect to Brighton 1998 criteria (p<0.0001). There was a positive correlation between CTS and BJHS (r=0.59, p=0.0001). Consequently, we suggested that BJHS could be a predisposing factor for CTS or vice versa.