The purpose of this study is to better understand consumers attitudes toward dissimilar brand extensions. This study investigates the relative effectiveness of extremely dissimilar brand extensions through the examination of consumers' evaluations. Dissimilar brand extensions are manipulated in terms of thinking/feeling and (high and low) involvement dimensions based on the structure of FCB Grid, and four brands(IBM, Chanel, Tylenol, and Starbucks) are selected for the study. The results indicates that symbolic parent brands in the category of feeling product brings more positive effects toward dissimilar brand extensions compared to functional parent brand in a thinking product category. Further, parent brands in the product category of high involvement produces more positive consumers' attitudes toward dissimilar brand extensions than low involvement product's brands. In addition, this study shows the influences of attitude and involvement toward parent brands on the attitude toward extended brands. Theoretical and managerial implications of the findings are discussed.