Objective Through the field epidemiological investigation of the first case of melioidosis in Huainan City,find out the possible infection sources and transmission routes,and further evaluate the risk of the outbreak of melioidosis in Huainan City,so as to provide basic data for the prevention and control of melioidosis in the future. Methods Through face-to-face communication with the patient's family members and on-site investigation of the patient's home and surrounding environment,the field epidemiological investigation of the epidemic was carried out.At the same time,the possible infection environment of the patient was visited to search for possible infection sources and suspicious cases. Results The epidemiological investigation results showed that the two patients involved in the epidemic had stayed at home for two weeks before the onset of the disease,had no history of going abroad,no tourism history in Hainan,Guangdong and other places,no contact history with returnees,tourists to Hainan,Guangdong and other places,no contact history with sick animals (horses,cattle,sheep,pigs,etc.),no contact history with suspected contaminated water and dust,and no suspected source of infection was found. Conclusion According to the life history,onset time,clinical symptoms and laboratory results of the two patients,it is judged that the epidemic is an sporadic epidemic of suspected homologous exposure opportunistic infection of Burkholderia pseudomallei.