This study aims to examine effects of Innovation Diffusion Model and uses and gratifications Perspectives on smartphone user's intention in the ubiquitous circumstances. To verify their effects, this study develops a research model which includes three Innovation Diffusion variables and one individual innovativeness variables as an independent variables, three the uses and gratifications variables as a moderate variables and user intention variable as a dependent variable. This study also explores interaction effects of Innovation Diffusion model and the uses and gratifications model on customers' purpose of use under ubiquitous environment. The results of a survey revealed that Relative advantages & Compatibility, Innovativeness, Information motive, and Symbolic value variables anticipated the smartphone user's intention in the ubiquitous environment. In the interaction effects between two models, the results show that some variables have the relationships at a statistically significant. The implications of these results are also discussed.