The guidelines for nutritional screening of head-and-neck cancer patients were systematically searched and screened from BMJ Best Practice, National Comprehensive Cancer Network, Britain's National Institute for Health and Clinical Excellence, National Guideline Clearinghouse, Scottish Intercollegiate Guidelines Network, Guidelines International Network, New Zealand Guidelines Group, Australian National Health and Medical Research Council, Medlive, PubMed, Embase, CINAHL, China Biology Medicine, VIP, Chinese National Knowledge Infrastructure, and Wanfang. Four researchers evaluated the quality of the included literature and extracted evidence from the literature that met the quality standards. Finally, a total of six guidelines were included and ten best evidences were concluded. As only one guideline in this study is from China, and the rest are from other countries, the applicability and effectiveness of some evidence in the Chinese population still need to be further explored and studied. Therefore, when using evidence, medical staff should make appraisal on working environment in their hospital, factors that facilitate or hinder the use of evidence, and willingness of patients, and thus scientifically provide the best evidence for the management of clinical nutrition for head-and-neck cancer patients and provide a reference for the establishment of the standard process of nutritional screening for head-and-neck cancer patients.