After defining the determining factor of an attitude on clothing web-site as cognitive responses and affective responses, this study was to investigate how it affects against web-site attitude, brand attitude and purchase intention. To accomplish research subject, this study had an analysis on web-site attitude, brand attitude and purchase intention after selecting 3 department stores having mega fashion malls which run web-sites. Aad(Attitude toward an advertisement) was defined as cognitive responses and affective responses. This research analyzed it by multiple regression analysis after collecting a date from 265 customers who use 3 department stores selected The findings are as follows. First, Aad had a significance impact on web-site attitude across the department stores. Second, Aad had a significance impact on brand attitude across the department stores. Third, Aad had a significance impact on purchase intentions across the department stores. At the end of this paper, discussion, managerial implications, limitations, and future research directions were suggested.