Early diagnosis of entrapment neuropathies is important for the recovery of nerve functions. Imaging methods provide a useful diagnostic aid to clinicians about nerve and cause of entrapment. Ultrasonography should be the first preferred imaging method which is an easily accessible, cheap, rapid, and noninvasive imaging technique; it also demonstrates nerve itself. Ultrasonography can be used not only in diagnosis of entrapment neuropathies, but also as a guide during treatment. The purpose of this article is to demonstrate the ultrasonographic findings in the most common nerve entrapment syndromes, and to give basic information about the peripheral nerve ultrasonography.