In 2014, over 23 million individuals were playing massive multiplayer online role-playing games (MMORPGs). In light of the framework provided by Davis's (2001) cognitive-behavioral model of pathological Internet use, social anxiety, expressions of true self, and perceived in-game and face-to-face social support were examined as predictors of Generalized Problematic Internet Use Scale (GPIUS) scores and hours spent playing MMORPGs per week. Data were collected from adult MMORPG players via an online survey (N = 626). Using structural equation modeling, the hypothesized model was tested on 1 half of the sample (N = 313) and then retested on the other half of the sample. The results indicated that the hypothesized model fit the data well in both samples. Specifically, expressing true self in game, higher levels of social anxiety, larger numbers of in-game social supports, and fewer supportive face-to-face relationships were significant predictors of higher GPIUS scores, and the number of in-game supports was significantly associated with time spent playing. The current study provides clinicians and researchers with a deeper understanding of MMORPG use by being the first to apply, test, and replicate a theory-driven model across 2 samples of MMORPG players. In addition, the present findings suggest that a psychometric measure of MMORPG usage is more indicative of players' psychological and social well-being than is time spent playing these games.