Introduction: Malnutrition remains a public health problem and its prevalence varies between 20% and 50% in the population depending on the criteria used for its evaluation, and it can be even higher in cases of the elderly and in the presence of wasting diseases. Patients who have head and neck cancer of the upper aerodigestive tract, which includes the larynx, pharynx and mouth, have an increased risk of malnutrition, given genetic factors and previous habits, arising from the abusive consumption of alcohol and tobacco, and also, by the impact on food intake due to the location of the tumor or the treatment to which it will be submitted. Objective: To evaluate the nutritional profile of patients with head and neck cancer undergoing surgical treatment.Method: Twenty-one patients from the discipline of head and neck surgery were selected, submitted to nutritional, biochemical, anthropometric and bioimpedance assessment before and after surgery. Patients without operative conditions were excluded from the study. Result: For the classification of nutritional status, three evaluation methods were considered, body mass index (BMI), arm circumference (AC), arm muscle circumference (AMC) and laboratory examination. In the pre-op, 14% of the sample had moderate malnutrition, in the post-op, moderate malnutrition remained at 14% and 5% were severely malnourished according to BMI. Pre-op considering CB, 10% moderate malnutrition and 15% mild malnutrition, in the post – op 33% mild malnutrition, 10% moderate malnutrition and 5% severe malnutrition. Pre-op considering CMB, 5% mild malnutrition and post – op 48% moderate malnutrition, 14% mild malnutrition and 19% severe malnutrition. Bioimpedance pre-op lean mass, 11% below, post-op 24% below the recommendation and 5% not detected due to the sensitivity of the scale for BMI below 18kg/m2. Regarding laboratory tests, C-reactive Protein, Iron, Ferritin, Creatinine altered in the pre-op and post-op, and Albumin altered only in the post-op Discussion: Laboratory tests remained altered in the pre and post – op, with attention to albumin markers that were altered in the post – op. Malnutrition in the post-op period increased in relation to the pre-op period and we can verify this change mainly when we compare the percentage of lean mass, using the method of evaluating arm circumference and arm muscle circumference associated with bioimpedance data. The prevalence of proteinenergy malnutrition in the group studied in the postoperative period, taking into account the classification for muscle circumference of the arm, observed moderate malnutrition in 48%, 19% severe malnutrition and 14% mild malnutrition, only 19% remained in eutrophy, with adequate nutritional status. Conclusion: The patients with head and neck cancer with squamous cell carcinoma of the upper aerodigestive tract, who were selected for surgical treatment, in the preoperative period had an acceptable malnutrition rate, but when we compared the postoperative period, we observed that there was a worsening, it increased the percentage of protein energy malnutrition. Surgery had an impact on nutritional status and there was a correlation between complications and malnutrition. These data indicate that a nutritional intervention should be carried out to achieve better results.