Objective Drug abuse is an escalating problem in Hong Kong, especially among teenagers and young adults. A study was conducted in order to obtain the characteristics of drug abusers presenting to the Accident & Emergency department of North District Hospital, which is located in the New Territories near the Hong Kong – Shenzhen border. Design Prospective study. Setting Accident and Emergency department of a public general hospital. Patients Drug abusers presenting to the Accident and Emergency department in a six-month period. Main outcome measures Epidemiological data including demographic data, types of drug taken, place of drug abuse and magnitude of cross-border drug abuse were collected and analyzed. Results The sex distribution was male 59 and female 13 (ratio=4.5:1). The mean age was 29.2 (range 14 to 67 years). Of interest, 29.2% abused drugs at home; 29.2% abused drugs in parties such as karaoke, rave and disco; 68% abused drugs in Hong Kong; 32% abused drugs in China and 6.9% claimed themselves first-time drug abusers. The commonest drug taken was ecstasy (40.3%) – the majority (55%) in China and the rest (45%) in Hong Kong. For organic solvent abusers, 57.1% were below 18 years of age. One patient died, resulting in a mortality rate of 1.4%. Conclusion Ecstasy was the commonest drug abused on both sides of the “border”. The majority of substance abusers were teenagers or young adult males. This study confirmed the significant magnitude of psychotropic substance abuse problem among the young population in the North District, indicating the urgent need for clinical and social intervention.