Janni Leung

Dr Janni Leung is an epidemiologist of addiction, substance use and mental health, and NHMRC Emerging Leadership Fellow at the National Centre for Youth Substance Use Research, at The University of Queensland. She is studies how substance use and mental health affect people and communities, and how research can help prevent harm.

Janni has published more than 200 papers, attracting over 15,000 citations, with 30% of her research among the world’s top 1% most cited. Expertscape ranks her among the top three cannabis researchers in Australia and the top 10 globally. She was jointly named Queensland’s 2025 Young Tall Poppy of the Year, —the award’s highest honour across all scientific fields—and was recognised by The Australian’s Research Magazine as one of 40 early-career researchers to watch.

Her research spans cannabis, alcohol, nicotine and vaping, mental health, and digital addictions such as gaming disorder. She uses epidemiological studies, systematic reviews and statistical methods to understand emerging problems and inform policy and prevention. Janni values strong partnerships with communities and meaningful involvement of consumers and people with lived experience, including co-designing innovative public health interventions with young people and parents.

Research supervision

Janni has experience supervising students from public health, psychology, medicine and diverse cultural and life backgrounds. She can supervise coursework research projects, master’s theses and PhD research. She welcomes students who are self-motivated, reliable, open to feedback and with a strong comitment to rigorous high-quality research. Prospective students should email a brief cover letter and CV; international applicants should also provide their IELTS English-language test results. Supervision is considered based on research fit, preparedness and available capacity.