Purpose: The purpose of this study was to evaluate the quality of service and appropriateness of information provided in gastric cancer web sites. Method: The study investigated the status of the web sites retrieved when the keyword "gastric cancer" was searched on seven(7) different Internet portal sites. Among the retrieved information sites, 51 domestic websites, available on June and July 2008, were selected. They were evaluated based on two criteria, quality of service (7 items) and appropriateness of the information (11 items) on a 4-point scale($0{sim}3$). The analysis of data was done using SPSS 12.0 PC+ program for descriptive statistics and ANOVA tests. Results: Findings revealed that the quality of service provided by the web sites had an average of $1.61{pm}.55$. The score of information appropriateness was $.79{pm}.64$. Among the studied websites, only 4(7.8%) scored higher than 22, placing them in the top 30%. Conclusion: This study suggests that most sites do not provide diverse types of gastric cancer-related information and that reliability is important in developing web-based programs related to gastric cancer in order to effectively promote and disseminate health information to the general public.