Superficial venous malformations can be clinically diagnosed since birth as localized, bluish or purple lesions, especially on the lower extremity, but deep venous malformations are difficult to diagnose only by clinical appearance. The diagnostic algorithm for superficial venous malformations in newborns includes clinical examination and Duplex ultrasonography. The latter allows differentiating tumors (hemangiomas) from vascular malformations and evaluating flow characteristics as well as localizing the site of the malformation.