Internet gaming disorder (IGD) was regarded as behavioral addiction, and the common characteristics of internet addiction (IA) or IGD were craving, tolerance, withdrawal, mood modification, and salience. The fifth version of Diagnostic and Statistical Manual of Mental Disorders, addressed IGD, and also proposed 9 research criteria for IGD in 2013. Emotion was reported one character of IGD, and this study hypothesized that emotion was both a response and an influential factor on IGD. The self-report for emotion and questionnaires (psychological character), and electrocardiography (ECG) (physiological signal) of participants in emotional state were collected and analyzed in a non-invasive manner. An emotional induction experiment using online game film clips was conducted. Nineteen participants were grouped into IGD& high-risk internet addiction group, and 21 were in non-IGD & low-risk internet addiction group. The physiological signal (ECG) was used to study emotional responses of IGD. The sympathetic and parasympathetic activities were obtained from heart rate variability (HRV). The IGD addicts exhibited more positive emotion, and stronger sympathetic activity, but felt weaker physiological activity for online game than non-IGD addicts. Emotion can provide a short-term, quick response and dynamic changes of psychological and physiological information of IGD addicts, and that allowed researcher to develop further application, such as monitoring system, early alarm system, early IGD detection, and even prevention.