Abstract： Objective:To explore the clinical characteristics of poisoned patients with poisons purchase online.Methods:A retrospective case-control study was conducted on poisoned patients purchased poisons online from 1st January 2021 to 31th May 2022 in the Emergency Department of the First Affiliated Hospital of Nanjing Medical University. The clinical data including sex, age, way of medical treatment, cause of poisoning, exposure routes, category of toxic drugs, gastric lavage, toxic detection and prognosis of patients were collected and compared with those patients obtained poisons at stores as the control group.Results:Totally 318 poisoned patients were included in this study, of which 44 (13.8%) were obtained poisons online. Compared with the patients obtained poisons at stores, the patients obtained poisons online were younger ( P<0.001), and had higher proportion of suicide intention ( P=0.006), more oral route exposure ( P=0.029), and more proportions of receiving gastric lavage before transfer to the hospital ( P=0.001). Pesticides and fertilizers with organic heterocycles were the main types of poisons in the online group, and there was no statistical difference in the distribution of poisons compared with the control group. Mixed drug poisoning was the leading cause in both online group (27.8%) and control group (38.8%) in drug overdose poisoned types, followed by dextromethorphan (16.7%) and estazolam (15.5%) in the online group. Conclusions:Young people are the main group getting poisons through the Internet. Health education should be strengthened for this group, and online shopping platforms should pay attention to the poisoning risk of potential overdose drugs or poisons transactions.