This study examines the factors influence learner' self-efficacy, such as perceived behavioral control and motivation, as well as moderating effects of gender, disciplines, and social influences. Blended learning reform in China was first stared in engineering majors and developed relatively mature, which became one of the models for other majors` reform. Blended learning has been a major goal of higher education curriculum reform in recent years, whereas the role students play in it is not discussed enough in China, including their subjective feelings and emotions, such as self-efficacy. Data was collected through an online questionnaire from a total of 500 undergraduates from Chengdu who have had blended learning experiences in the past year. Results indicate that both perceived behavioral control and motivation are significant predictors of self-efficacy. Gender plays a significant moderating role, while disciplines does not. When gender, disciplines, and social influence were considered together, influences from family and teachers and peers exerted different moderating effects, respectively.