Background: One of the easiest sign to identify during chest sonography is the movement of the visceral pleura compared to immobility of the parietal pleura. This sign of ‘pleural sliding', firstly described in veterinary medicine and was used to exclude the presence of pneumothorax when present and to suspect atelectasis, fibrosis or pleural adhesions (pleurodesis) when absent. Aim of the Work: This study aims to detect successful pleurodesis with povidone-iodine in patients with malignant pleural effusion by using the chest ultrasonography. Subjects and Methods: This study was carried out on 30 patients with malignant pleural effusion attended to AL-Hussein University hospital, Al-Azhar University in the period between October 2017 and May 2018.All patients underwent full history taking, complete clinical examination, plain chest X-ray, routine lab investigations, CT scan of the chest, pleural fluid analysis including physical, chemical, Bacteriological and cytological examination for malignant cells, medical thoracoscopy, transthoracic ultrasonography before and after pleurodesis to assess the presence or absence of sliding sign. Results: The results of this study revealed that the transthoracic ultrasound can easily detect sliding sign and assess the success of pleurodesis. Iodopovidone was effective in inducing pleurodesis in patients with malignant pleural effusion. Conclusion: Transthoracic ultrasound for the evaluation of pleurodesis is feasible and simple.Iodopovidone was effective in inducing pleurodesis in patients with malignant pleural effusion.