Carpal tunnel syndrome (CTS) is reveled to be the most common peripheral nerve entrapment syndrome, estimating for 90% of all compressive. The diagnosis of CTS is based on the use of clinical criteria and imaging technique tests such as ultrasonography (US) and magnetic resonance imaging (MRI). US is a time-saving method in the diagnosis of CTS, which induces less discomfort to the patient and may be a more cost-effective approach to confirm clinical suspicion of this syndrome .The current study was aimed to evaluate the value of US and physical examinations in the diagnosis of CTS. This cross-sectional and cross-sectional prospective case study was conducted to evaluate the usefulness of wrist ultrasonography in diagnosing CTS. Twenty one patients (21 wrists) were invited to participate in the study along with an age- and sex-matched group of participant controls. Physical examination included Phalen, Tinel, Durkan, Tourniquet test. Anteroposterior and mediolateral dimension of carpal tunnel, and the median nerve area at the tunnel were also measured. All the patients underwent the open surgical release of the flexor retinaculum. There was a significant statistical relationship (p=0.05) between anteroposterior diameter of the carpal tunnel and clinical and electro physiologic nerve involvement. Furthermore, some qualitative findings was achieved such as median nerve splitting, hypo echogenicity of the involved nerve, thickening of flexor retinaculum and disappearance of median nerve areas (especially mediolateral direction). In conclusion, ultrasonographic examination of the wrists in the patients with suspected clinical symptoms can improve the diagnostic ability of CTS, especially by improving technology and experience. US can be applied for the median nerve area (MNA) measurement as a first line technique in patients with CTS.