The aim of the study was to investigate the relationship of Internet addiction (IA) severity with alexithymia, temperament, and character dimensions of personality in university students while controlling for the effect of depression and anxiety. A total of 319 university students from two conservative universities in Ankara volunteered for the study. Students were investigated using the Toronto Alexithymia Scale-20, the Temperament and Character Inventory, the Internet Addiction Scale, the Beck Anxiety Inventory, and the Beck Depression Inventory. Of the university students enrolled in the study, 12.2 percent (n=39) were categorized into the moderate/high IA group (IA 7.2 percent, high risk 5.0 percent), 25.7 percent (n=82) were categorized into the mild IA group, and 62.1 percent (n=198) were categorized into the group without IA. Results revealed that the rate of moderate/high IA group membership was higher in men (20.0 percent) than women (9.4 percent). Alexithymia, depression, anxiety, and novelty seeking (NS) scores were higher; whereas self-directedness (SD) and cooperativeness (C) scores were lower in the moderate/high IA group. The severity of IA was positively correlated with alexithymia, whereas it was negatively correlated with SD. The "difficulty in identifying feelings" and "difficulty in describing feelings" factors of alexithymia, the low C and high NS dimensions of personality were associated with the severity of IA. The direction of this relationship between alexithymia and IA, and the factors that may mediate this relationship are unclear. Nevertheless, university students exhibiting high alexithymia and NS scores, along with low character scores (SD and C) should be closely monitored for IA.