Trade Portal Site(TPS) is one of the essential tools which can make it possible for small and medium enterprises(SMEs) to perform international trade activity more efficiently using newest information and communication technology including the Internet. Therefore, Korean SMEs need to utilize TPS more actively to enhance their export competitiveness. In this context, this article analyzes the determinants of export performances of Korean SMEs in utilizing the service of TPS based on the Service Quality Model. As a result of an empirical research by using regressive analysis, various measures of service reliability such as reliability, empathy, and tangibilities have positive effects on SMEs export performance in utilizing TPS. These results provides many useful implications to the TPS managers, e-trade related government agency, along with managers of SMEs using TPS.