Objective A dichroine poisoning outbreak caused by the accidental ingestion of fresh Dichroa yunnanensis was investigated and resolved， which can provide scientific support for the clinical treatment and further prevention of dichroine poisoning.Methods A systemic epidemiological investigation， hygiene investigation， laboratory tests， morphology analysis， and molecular identification of the plant were conducted soon after the incident， and poison treatment consisted of evaluating clinical symptoms， giving therapeutic drugs， and achieving a patient cure.Results Based on the botanical and molecular biological identification results of Dichroa yunnanensis， the sample involved in the poisoning incident was confirmed to be Dichroa yunnanensis， Yunnan Province. The toxic substance responsible for the poisoning was an alkali from Dichroa yunnanensi， with a 100% effect rate among individuals who consumed it. Clinical manifestations included mainly nausea， vomiting， diarrhea， tenesmus， and other gastrointestinal symptoms， which abated within 24 h of fluid rehydration， stomach protection， potassium supplementation， and broad-spectrum detoxification treatment， without additional symptoms.Conclusion This incident of dichroine poisoning was caused by the accidental consumption of fresh Dichroa yunnanensis. As no D. yunnanensis poisoning case has been reported previously in China， this report has important reference value for the prevention and clinical treatment of similar poisoning events in the future.