Motivating tourists’ responsible behaviors during their trip has emerged as an essential yet insufficient investigated topic in sustainable tourism research. Ration-based and socialization-based motivators have to be integrated to address the lack of a holistic antecedent framework of responsible tourism behavior. Thus, this study extended the unified theory of acceptance and use of technology (UTAUT) into responsible tourism behavior learning and combined the theory of social influence to establish an extensive socialized model of UTAUT to explain tourists’ adoption of responsible behavior behaviors. This model includes three tourism elements—sustainable benefits, sustainable facility accessibility, social interaction engagement as antecedents, and two types of mediators: ration-based mediators of performance expectation and effort expectation and socialization-based mediators of informative influence and normative influence. 491 Chinese tourists were surveyed to confirm this model. It is found that all four mediators explain tourists’ responsible behaviors. Moreover, sustainable benefits positively influence tourists’ performance and effort expectation and social interaction engagement positively influences informative and normative influences, while sustainable facility accessibility positively leads to effort expectation and normative influence.