The purpose of this study was to determine the best model fit among the six models in the Korean version of Positive and Negative Affect Schedule (K-PANAS). Therefore, this study compared and analyzed the dimensional structure of this schedule for Korean college students. Specifically, the model fitness of six models, which are under debate, were compared: a single model for K-PANAS, a two-factor model (PA&NA) without any factor correlation, a three-factor model (PA, NA-Afraid, NA-Upset), a two-factor bifactor model, a three-factor bifactor model, and a three-factor bifactor model with error correlation. A total of 875 samples were analyzed, and the results show that best model fit is the three-factor bifactor model with error correlation. We named the general factor of the bifactor model “activation (or arousal).” This findings of this study will provide a richer explanation of emotions for researchers analyzing emotional activation (or arousal), a general factor of emotion, PA, and NA future studies that use PANAS.