Tourism is one of the major sources of income for many countries and with the advent of internet, using this new channel (internet) for providing different services of tourism, i.e., e-tourism, is growing rapidly. This is also the case in Iran, but it is clear that focusing on technology alone can’t lead the business to success. The key point of successful business in e-tourism is to concentrate on the customers and their behavior for having a better relationship with them. This study is intended to develop a model based on Decomposed Theory of Planned Behavior (DTPB) that considers influential factors to predict and evaluate intention of tourists and travelers while using e-tourism services and websites, such as www.expedia.com and www.priceline.com. The influential factors are studied and investigated through a survey with 259 responses. Structural Equation Modeling (SEM) has also been utilized for testing relevant hypotheses to either include or thwart specific factors which drive people to use e-tourism services provided in e-tourism websites. The results show that “Subjective Norm” and “Perceived Behavioral Control” significantly affect Iranian customer’s intention to use e-tourism (i.e., the websites which offer tourism services). In this research we not only worked on evaluating a model and the relationship between constructs, but also tried to find specific factors that drive people to use e-tourism. So, besides DTPB factors, we found that Curiosity has more effect on tourist intention. The findings have implications for Iranian tourism companies to predict the behavior of tourists when they are using the e-tourism, and also develop the CRM methods in e-tourism websites.