There has been an increase in the frequency of substance abuse among hospitalized burn injury patients. However, few studies have investigated substance abuse among burn patients. This study was aimed to identify the incidence of substance abuse in burn injury patients using the "Drug Abuse Screening Test" (DAST-20). We determined the validity of DAST-20 in spring 2010. Subsequently, this descriptive study was performed on 203 burn injury patients who fit the study’s inclusion criteria. We chose a score of 6 as the cutoff and thus achieved a sensitivity of 89% and a specificity of 85% for the DAST-20. During the study, we gathered demographic data, burn features and DAST-20 results for all patients. Patients with scores of 6 or more were considered to be substances abusers. A statistical analysis was conducted using SPSS v16 software. According to the DAST-20 results, 33% of the patients were in the user group. The mean score of DAST-20 was significantly higher among users than it was among nonusers (P<0.05). The level of substance abuse was severe in 77% of users. No significant differences were found among the substances, with the exception of alcohol. Substance abuse is an important risk factor for burn patients. In addition, this study showed that DAST-20 is a valid screening measure for studies on burn patients.