It was aimed to investigate the relationships of self-esteem, loneliness, social support, and alexithymia with Internet addiction in this study. It was expected that the psychosocial variables of the study that were utilized together in this study due to their possible common connections with social skill and online communication preference would be associated with Internet addiction. Moreover, it was hypothesized that alexithymia would be associated with Internet addiction after controlling for the effects of the other psycho-social variables, gender, and Internet usage duration. Thus, it was aimed to test the increased role that has begun to be attributed to alexithymia in relation to the Internet addiction. The sample of the study was composed of 204 female (53.5%) and 177 (46.5%) male university students, 381 participants in total. All variables investigated in the study were correlated with Internet addiction. In line with these findings, the group composed of participants with higher Internet addiction scores, scored lower on self-esteem and social support, higher on loneliness and alexithymia as compared to the group composed of participants with lower Internet addiction scores. Moreover, self-esteem and loneliness that were entered into the equation in the second step, alexithymia that was entered into the equation in the third step following gender and Internet usage duration that were entered into the equation in the first step were associated with Internet addiction according to the results of the regression analyses. Especially internet usage duration and alexithymia were observed as robustly associated with Internet addiction.