Effective development of e-commerce requires the internet and websites as the most important tools. The internet has been widely used since 1994 and e-commerce has been contributing to its growth in many countries. Although there are opportunities for e- commerce growth, it has not achieved its full potential in Vietnam. Based on the research of Chen (2007) and Meziane and Kasiran (2008), this study examined 4 factors affecting consumer’s trust in e-commerce: Affiliation, Existence, Policy, and Website Design. An analysis of 240 surveys found that affiliation of website, policy of website, and website design attitude of company were significant predictors of consumer’s trust. Discussion, implications, limitations, and recommendations are provided in this study.