Anesthesia requires informed consent because it is an invasive procedure with certain risks. However, the state of informed consent for anesthesia in Japan remains unclear. The purpose of this survey was to examine the state of informed consent for anesthesia in Japan. A questionnaire was sent to all hospitals certified by the Japanese Society of Anesthesiologists (n = 854). The questionnaire consisted of four sections: explanation of the anesthesia, method of documentation, consent for anesthesia, and other information such as the hospital's size. A total of 504 (59.0%) questionnaires were completed and returned. At 96.7% of hospitals, an anesthesiologist would explain the scheduled anesthesia. Most departments provide an explanation of dental damage, malignant hyperthermia, and nausea/vomiting. Explanation of anesthesia was standardized at 59.0% of hospitals. A written description was handed out to patients routinely at 61.3% of hospitals. Although consent for anesthesia was obtained at more than 90% of departments, only 59.9% of departments would keep records of having obtained consent. This survey found that the explanation of anesthesia varied among hospitals and was not standardized in Japan. Further attention is needed on how to improve the documentation of informed consent.