The purpose of the study was to assess the incidence of alcohol and amphetamine use among long-distance truck drivers. There were studied 91 truck drivers at the gas station in Passos, Southeastern Brazil, in November 2005. Data was collected using a questionnaire comprising 19 multiple choice questions. Descriptive statistics, Chi-square test and Cramér's correlation coefficient were used for data analysis. The results indicated that 66% of the long-distance truck drivers used amphetamines during their travels, mainly at gas stations along the highways (54%). Alcohol was consumed by 91% of them and 43% of them consumed it at gas stations. It is concluded that there is a need of preventive and education campaigns targeting this occupation category at gas stations and transportation companies, focusing on the risks of these substances' use during working hours.