Fibromatosis is a rare, benign, slow-growing and locally infiltrative tumour, caused by uncontrolled proliferation of fibrous tissue arising from muscles, connective tissue, fasciae and aponeurosis. It is also called desmoid tumour, which is very rare pathology representing only 0.03% of all neoplasms in human and around 3% of all soft tissue tumours. It is locally aggressive and usually invades the surrounding structures and has a high recurrence rate, even after surgical complete resection, which should be the first line of treatment. Here, we report a very rare case of extensive and disabling fibromatosis tumour in a 38-year male, involving three compartments of the right side of the head, neck and chest wall, which was completely excised surgically and had excellent postoperative results with no morbidity.