Aim: In our work we have considered the problems related to the post-operative hospitalization in patients admitted to our ENT's department in the last 4 years. Material of study: Our observations refer to a sample of 155 patients suffering from head and neck tumors. Results: Regarding therapy, some drugs have been less effective to prevent post-operative infection: the ceftriaxone at the level of the oral cavity/oropharynx and ceftriaxone/pefloxacin at the level of the hypopharynx/larynx. Discussion: Post-operative infections in cancer surgery can compromise not only the surgical outcome but also be responsible for delays for any adjuvant treatments. Post-operative infections risk in head-neck cancer surgery drops from 30- 80 % to 20 % with perioperative antibiotic prophylaxis. Despite the introduction of pre-operative prophylaxis , according to guidelines, the number of post-surgical infections still remains high (40/61% of cases). It is important to know the intrinsic risk factors (related to the patient) and extrinsic (related to the external environment and the same procedure) to better understand how to prevent infections. Prolonged hospitalization can expose patients to the risk of hospital pathogens. Conclusion: We tried to outline a profile of head-neck cancer patients more likely to contract post-operative infections. We also compared the effects of various antibiotics administered before and after the onset of complications to suggest a therapeutic protocol. Key words: Antibiotics therapy Post-operative infectious, Prophylaxis in head and neck surgery