Can experiencing debate league enhance the learner’s debate efficacy? This study aims to determine the categories of debate efficacy and to analyze how the debate efficacy forms in the specific contexts. This survey was conducted on 74 debate participation descriptions, and 15 in-depth interviews, and analyzed with NVivo 8 program (qualitative research method program). Debate efficacy was coded as “emotional”, “cognitive”, “social” aspects. the number of coding frequency orders emotional, cognitive, social in a row. Emotional efficacy was embodied by ‘self-confidence’, ‘interest’, ‘the will to continue’, ‘controlling feelings’. Cognitive efficacy was specified as ‘argumentation training’, ‘debate strategy’, ‘expansion of background knowledge’, ‘school achievement’. Social efficacy was classified by ‘civility’, ‘interests of social issue’, ‘interpersonal relationship’, ‘finding potential power’. The positive debate efficacy codings were 375 and the negative ones were 34.