The overall number of drug abuse cases has been on the rise around the world, causing it a disaster in many countries. In this retrospective study, we analyzed the characteristics of 11,903 drug abuse cases in Beijing, the capital of China, in the perspective of age, gender, nationality, region, season, type of specimens and various drugs, respectively. The case information was collected by the national-level forensic toxicology laboratory, which belongs to the China University of Political Science and Law. It was shown that the overall number of drug abuse cases had increased sharply from 2018 to 2019 and had a decrease of 25% in 2020. The incidence of drug abuse cases involving men was much higher than that of the cases involving women. The adolescents and young adults accounted for the largest share of drug abusers in our study. Haidian, as a national center of scientific and technological innovation with global influence, had the largest percentage of toxic substance-related cases, and the change was more pronounced than other districts during the 3-year-period. Chaoyang was second to Haidian in the number toxic substance-related cases. As a key window of economic, Chaoyang had the highest number of foreigner drug cases. June to August had the highest number of drug abuse cases, while amphetamines, opioids, cannabis and cocaine were the most common toxic substances involved in the cases we detected. To our knowledge, this is the first study to provide an overall analysis of drug abuse cases in Beijing, China. The study indicated the presence of a wide number of drug abuse cases in the capital city and confirmed the threat for the public safety and health. Such forensic information can assist the government to devise intelligence-based preventive and repressive measures and policies.