Alexithymia components (difficulty identifying feelings, externality oriented thinking and difficulty describing) and addiction potential in university students. Two hundred and fifty students were selected by cluster sampling from Shahid Chamran University, Ahvaz, Iran. The scales used for this descriptive study were the 20-item Toronto Alexithymia Scale (TAS-20), the Assertiveness Self-Report Inventory (ASRI), the Arnett inventory of sensation seeking, and the Iranian Addiction Potential Scale (IAPS). Data were analyzed with statistical analyzer software SPSS-ver. 16. There were simple and multiple relationships between assertiveness, sensation seeking, Alexithymia, difficulty identifying feelings, externality oriented thinking and difficulty describing and addiction potential. Multiple regression analysis (stepwise method) showed that sensation seeking, difficulty identifying feelings and assertiveness had significant multiple correlations with addiction potential (F=24.25, p<0.001). The variables of externality oriented thinking and difficulty describing feelings were eliminated by the regression analysis. Variables such as sensation seeking, difficulty identifying feelings and assertiveness predicted addiction potential among university students. The most important implication of this research was to pay attention scientifically to these variables as the fundamental factors of this difficulty, rather than just emphasizing the cessation of drug or alcohol using.