Background: Refeeding syndrome (RFS) is a lethal condition of metabolic disturbances that arise from the sudden switch of metabolism from a state of starvation to one of nourishment. Quick recognition would reduce health complications. Physicians who are unaware of the syndrome will not identify and treat it. As nutritional risk is associated with the risk of RFS, physicians should be aware of it. Aim: To determine whether the physicians of King Abdullah Medical City (KAMC) in Makkah know of RFS and, if so, have skills in diagnosis and managing the syndrome. Methods: One hundred and fifty-nine physicians of KAMC were recruited in a cross-sectional study. They were asked to complete a questionnaire by face-to-face interview. The questionnaire was designed to capture physicians’ knowledge and ability to manage RFS based on the awarding of certain scoring points. Results: The level of knowledge among physicians had a significant association between knowledge and age (p = 0.021) and medical specialty (p = 0.010). Additionally, the most knowledgeable physicians were those who work in critical care (21.4%). Around 18% of physicians were not able to manage RFS. Conclusions: Lacking knowledge of RFS and how to manage it leads to critical life-threatening complications. Physicians need nutritional education to help them diagnose RFS and consult dietitians to avoid its complications.