The aim of this study is to examine online game addiction level among university students in terms of emotional schemas, agentic personality, and various variables (i.e. gender, type of game played, and accommodation). The sample group consists of 380 university students studying in Izmir province and playing online games during the school year of 2017 and 2018. The data have been collected through multiple tools that are Online Game Addiction Scale for University Students, Multi-measure Agentic Personality Scale, Leahy Emotional Schema Scale, and Personal Information Questionnaire. The data were analyzed by correlation analysis, t-test, one-way analysis of variance, and regression analysis in accordance with the hypothesis of the study. The result of regression analysis indicated that emotional schemas of uncontrollability, demand for rationality, rumination, dissimilarity, denial of emotions, validation, seeing emotions as dangerous, acceptance of feelings, consensus, and guilt predicted addiction significantly, whereas, emotional schemas of weakness against emotions and duration did not predict such an outcome. Additionally, as a result of the t-test, it was found that online gaming addiction levels differed significantly according to gender and that males had higher levels of online game addiction than females. Lastly, one-way analysis of variance resulted in finding the level of online gaming addiction significantly differed based on the type of game played, but it did not differ significantly based on where students lived.