This paper gives an overview of the sonographic possibilities to examine the canine stifle joint. Sonographic examination was performed in stifle joints of 30 dogs without any pathologic changes in the hind leg. The sonographic examination is presented with corresponding sonographical findings. For this indication a linear- and sector transducer with 7.5 Mhz was proved to be useful. The patellar ligament could be scanned very well by a linear transducer in a longitudinal section using a standoff pad. Both the lateral and medial meniscus could be inspected, as well as injuries of the menisci. As an indirect sign to a lesion, effusions of the joint were proved quite sensitively. The cruciate ligaments could not be demonstrated correctly with ultrasound. The ultrasonography is used for the investigation of the soft tissue structures as the completion of the radiology. The scanning diagnostic technique is practicable with a low technical expenditure, is not stressful for the patient and can be repeated for therapy controls: Disadvantageous is that ultrasound is prone to artifacts, caused by the thinness of the structures examined.