Objective To investigate an incident of mushroom poisoning in Chenzhou, Hunan province in June 2020, analyze the cause of the incident, and provide a basis for formulating prevention and control measures. Methods Epidemiological investigation was carried out to find the cause of poisoning. The samples of suspicious poisonous mushroom were collected for morphological identification, and the mushroom toxin and blood samples were determined by LC-MS. Results There were 7 cases of mushroom poisoning and 1 death. All the patients ate wild mushrooms picked up by themselves, and the incubation period was 14-23 h. Early clinical manifestations included vomiting, abdominal pain, diarrhea and other gastrointestinal symptoms, which led to progressive liver damage and death in severe cases due to acute liver failure. Blood biochemistry showed abnormal elevation of alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase. The remaining wild mushrooms collected on site were identified as Amanita fuliginea by morphological identification and mushroom toxin test. Conclusion This was a mushroom poisoning incident caused by the accidental ingestion of highly toxic Amanita fuliginea. Publicity on mushroom poisoning should be strengthened. Rapid screening technique of mushroom toxin and Foodborne Disease Surveillance Network should be improved to reduce the incidence of mushroom poisoning and death.