The current study examined whether and how players’ aggression is affected by playing games focused on Intrapersonal level of player. In contrast to most existing studies, our study asks about crucial underlying factors among the general game population and thereby investigates mental health belief, interdependent and independent self-construal, game-efficacy, loneliness, depression, gender and age. Results show that mental health belief is particularly important to the players because their aggressive tendencies are greatly diminished. Independent self-construal and game efficacy reduced the levels of players’ aggression. Interestingly, both depression and loneliness decreased the levels of players’ aggression. Results and implications are discussed.