Aim. The present study investigates the evolution of illicit drug use among Romanian university students from 1999 to 2011. Methods. The study was performed in Cluj-Napoca, Romania, in three phases: in 1999 (T1), in 2003 (T2) and in 2011 (T3). The study was carried out by means of anonymous questionnaires among university students aged 19-24. Results. The results show that among girls the lifetime illicit drugs use increased statistically significantly from 2.5% in 1999 to 7.5% in 2003 and to 15% in 2011. Among boys the trend was also increasing, the prevalence of illicit drug use was 14.2% at T1, 18.1% at T2, and it increased dramatically to 30.6% at T3. The percentage of students reporting cannabis use was almost identical with the total prevalence of illicit drug use. Ecstasy was the second most frequent drug used by the students; its consumption had also an increasing trend during the examined periods (from 0 to 5.6% among girls and from 0.8% to 11.2% among boys). The results of the bivariate correlation analyses show that lifetime illicit drug use was associated with having friends who experimented with illicit drugs both among boys and girls. Moreover, girls who declared stress management problems and depressive episodes were more likely to try illicit drugs, while among boys illicit drug use was associated with poorer academic performance. Conclusions. The data pointed out by our study call for comprehensive actions regarding the prevention of illicit drug use among Romanian young people.