The purpose of this study is to investigate the effects of the prior knowledge, the market position and negative information of the alliance apparel product on consumer attitude including preference, purchase intent and utility. Smart wear with MP3 was selected for the alliance apparel product. Negative information was manipulated into two types-product related and brand related negative information. 251 subjects participated for the study. For the data analysis, reliability test and three way analysis of variance were conducted. The results showed that when the partner brand has the higher market position, subjects with high prior knowledge revealed preference for the alliance apparel product more. When the partner brand has the higher market position, the subjects who were given the negative information on the alliance apparel product reported preference and utility more than the ones who were given the negative information on the company. The findings of the study imply that apparel industries should make an effort to establish the positive corporate image as well as to produce high quality apparel product. Also marketers should provide consumers with the knowledge about brand new alliance apparel product.