The study was with the relationship among 8rand Credibility, Perceived Quality, Perceived Risk, and Information Search which were proposed by Erdem and Swait (2004) to be the basis of this thesis. The study investigated on the difference of brand credibility, perceived quality, perceived risks and information search that consumers have toward cosmetics under different humanities variables. It also verified the correlation of cosmetic brand credibility and further probed the comparative influence of cosmetic brand credibility, so the results may be used as the reference for future strategy planning. Then it analyzes the information by descriptive statistics, factor analysis, one-way analysis of variance and regression analysis. Focusing on the consumers residing in Taipei, Taichung and Kaohsiung, 3 urban districts, who have used Shiseido, SKII and Kanebo. A total of 816 valid questionnaires were collected, this study proposed the marketing strategies based on the results of statistical analysis.