Successful preoperative localisation of parathyroid glands is essential for minimal-invasive surgery of hyperparathyroidism. The knowledge of the sonomorphology of the parathyroid glands, therefore, is an important prerequisite. This article shows that the sonomorphology of normal and pathologically transformed parathyroid glands is subject to a wide variety. The often simplified standard description of parathyroid glands as hypoechogenic and oval may lead to false negative cervical ultrasound examinations.