In the fierce competition, a lot of companies and organizations started to realize that brands play a critical role in establishing a firm’s visibility and position in markets. As a result, more and more branding strategies are developed for the aim of gaining competitive advantage in the marketplace. As one effective branding strategy, the use of co-branded products has gained increasing attention from marketers and scholars.However, the purpose of this study is to examine the major factors that affect consumers’ evaluations towards co-branded products. Based on a broad review of the brand alliance and co-banding literature, an empirical study was conducted to investigate the impact of pre-existing attitude towards parent brands, and perceived fit between parent brands on consumer evaluations towards co-brand.In this study, perceptions and evaluations of a set of six actual brands and 4 hypothetical co-brands yield from the six was gathered from 255 consumers randomly. Data analysis was conducted by using statistics program SPSS and the following findings were obtained.First, attitude towards parent brands are significant related positively to consumers’ evaluations of the co-brand.Second, perceived fit between parent brands which including product category fit and brand image fit, plays a key role in consumers’ evaluations of the co-brand.Third, the relationship between parent brand attitudes and co-brand evaluations is moderated by perceived fit between the two parent brands.