The purpose of this study was to compare the effects of internet fashion advertisement (Ad) formats according to university students' online lifestyle. Static banner, rich media, floating, shopping, and target advertisement were selected as stimuli and a self-administered questionnaire was used for data collection. SPSS PC (Ver. 16.0) was used for factor analysis, ANOVA, and Chi-square test. Factors of online lifestyle were economy, early adaption, cyberspace activity, sociability, innovation, and entertainment, and subjects were segmented into online activity (OA) retard group, OA mania group, hedonic early adapter group, and OA intermediate group. OA retard group was positive to a static banner Ad with intimacy, and OA mania group and OA intermediate group were positive to a static banner Ad with confidence, attention, and intimacy and rich media Ad and floating Ad with confidence and attention. Hedonic early adapter group was positive to a target Ad with attention and intimacy. Internet shopping mall managers should select internet Ad format after segmenting their customers according to OA lifestyle.