Endolaryngeal spread of laryngeal malignant tumours is usually determined by conventional endoscopy; however, it can not measure the outward extension of the tumour. As an alternative method for assessing the extension of a tumour and detecting metastatic lymph nodes, we have introduced high-resolution ultrasonography (US) in 34 patients with laryngeal epidermoid carcinoma. The ultrasonographic results were compared with the clinical, operative and histological findings. The ultrasonography revealed malignant extensions in the thyroid cartilage in nine cases, in the carotid artery in four cases, and in the thyroid gland in five cases. These were confirmed by surgical and histopathological examinations. Six patients out of the 34 were subclinical cases, who had metastatic lymph nodes, which were diagnosed by US only. In this study US had a sensitivity of 94.44 per cent and a specificity of 93.75 per cent. The sensitivity and specificity of palpation of the cervical lymph nodes were 66.66 per cent and 87.55 per cent respectively. It may be concluded that high-resolution real-time US is a sensitive, simple and inexpensive method for evaluating laryngeal cancers and subclinical cervical lymph node metastasis.