BACKGROUND: Preoperative fasting is a requirement to be made by anesthesiologists, but they generally depend on nurses to ensure it is carried out by patients. Lack of updated knowledge among nurses may cause complications. METHOD: The objective of this study was to understand the knowledge of nurses about preoperative fasting. The multi-unit study was conducted in the units of our hospitals using an Internet-based survey. The responders were anonymous to the authors. RESULTS: The survey was sent to approximately 5,000 nurses, with more than 600 responding to the survey. Most of the respondents were aware of the preoperative fasting guidelines. The understanding regarding preoperative fasting appeared to be insufficient among nurses. The nurses appreciated the concern of the anesthesiologists about fasting. The nurses opined that additional training regarding preoperative fasting might benefit them. CONCLUSION: This survey conveyed to the authors that the nurses of our hospitals were knowledgeable but required further training to update them. J Contin Educ Nurs. 2018;49(3):127-131.