Electronic commerce, as the new era of commerce in 21st century, not only has revolutionized the traditional commerce but also changed people’s lives. However, like any other new product or service, it faces many problems to attract its own users. Users in different countries with different cultures, have different needs and demands, and they react differently when facing new products or services. Understanding the culture of electronic commerce users is a great help toward perceiving the reason why they act differently. This study is trying to understand the effect of Iranian national culture on users’ behavior while using electronic commerce. The framework of the research is based on Hofstede’s national culture model, and it is trying to investigate the relation between every variables of the model and electronic commerce users’ behavior in Iran. Research method is descriptive and analytical. The results show that uncertainty avoidance and collectivism are two important factors, which are affecting the behavior of electronic commerce users in Iran.