The overall aim of the DUHEI Survey was to determine the prevalence and correlates of drug use among the student population in the Republic of Ireland, to inform future policy and practice in the area. The survey population included undergraduate and postgraduate students aged 18 years and over in publicly funded HEIs. The sampling strategy used ensured that a random representative sample of the student population was invited to participate in the survey. The questionnaire used validated scales where available and comprised 10 sections covering: Demographics; Student Life; Drug Use; Readiness to Change; Behaviour Change; Cognitive Enhancers; Student Wellbeing; Social Norms; COVID-19 and Drug Use; Drug and Alcohol Recovery. The DUHEI survey reports drug use prevalence data for different user groups defined by date of last drug use. These groups are never users; prior users (last used more than 12 months ago), recent users (last used in past 12 months), and current users (last used in past 30 days). Twenty-one publicly funded HEIs in the Republic of Ireland participated in DUHEI. Data collection was completed in early 2021 via a secure online survey platform. Over 11,500 participant responses were included for analysis of which 60% were female, the median age was 21; 81% were undergraduates, 9% were registered with a Disability Support Service, and 90% were EU students. The response rate to the survey was 29%