Head and neck tumors include nasal cavity, paranasal sinuses, lip, oral cavity, pharyngeal, laryngeal, salivatory glands and thyroid tumors. Most commonly, head and neck tumors develop from epithelial cells (squamos cell carcinoma). The most important risk factors for the development of the head and neck squamos cell carcinoma (HNSCC) are smoking, alcohol and human papillomavirus infection. First symptoms are usually nonspecific (painless lump in the neck, wound that does not heal) and therefore patient history and detailed examination are a key. When it comes to imaging procedures, the most information about the tumor site and its features is provided by multislice computed tomography and magnetic resonance imaging. The final diagnosis is confirmed pathohistologically. Approach to treatment, depending on the stage of disease according to TNM classification, can be surgical, conservative (radiotherapy and chemotherapy) or a combination. In case of the surgical removal of the tumor, the tissue defect can be closed in a several different ways, free flap reconstruction being the commonest one today. In head and neck surgery, radial forearm, fibular, rectus abdominis, iliac, scapular and anterolateral free flaps are used. Head and neck cancer patients are often malnourished. Malnutrition can affect the outcome of the treatment, postoperative complications and wound infections. Therefore, regular nutritional status assessment is required. The assessment can be performed by evaluating different anthropometric measurements and nutritional risk via different tools, such as the NRS2002 risk assessment tool. The most significant biochemical parameter for nutritional status assessment are albumin levels. Lower levels of albumin account for a higher risk of postoperative complications (prolonged wound healing, free flap failure, infection). Stress reaction of the autonomic nervous system following the operation can have a negative effect on the already malnourished patients. That is why nutritional support, in shape of instant formula, should be administered before and after an operation, in order to provide a better postoperative course and faster recovery.