This study was intended to identify the persuasion effects according to social proof message type and product type in the context of online cosmetic advertising. For the experiment, 4 stimuli were developed as experimental stimuli for the 2(social proof message type: attitudinal social proof message, behavioral social proof message)${ imes}$2(product type: hedonic product, utilitarian product) factorial design. A total of 160 questionnaires allocating forty students to each group were distributed. The results were as follows. First, behavioral social proof message showed more effective than attitudinal social proof message in advertisement attention, click-through intention and purchase intention. Second, utilitarian product showed more effective than hedonic product in advertisement attention, click-through intention and purchase intention. Third, there was interaction effect according to social proof message type and product type on the aspect of click-through intention.