With the rise of "Internet + Education," blended learning has become a new trend in higher education. This study aims to explore how behavioral willingness and self-efficacy affect the learning effect of college students in this new learning mode. The Unified Theory of Acceptance and Use of Technology (UTAUT2) was used to construct a theoretical model, and data on the blended learning effectiveness of 167 college students from a university in Southwest China were collected through questionnaires, and the theoretical assumptions and model were verified using Structural Equation Modeling (SEM) in Smart PLS software. It was found that in blended learning, performance expectation, effort expectation, hedonic motivation and facilitation all significantly and positively affect college students' behavioral intention of blended learning, which in turn positively affects the effect of blended learning, among which hedonic motivation is a more important influencing factor in the behavioral intention of blended learning. Self-efficacy also has a significant positive effect on blended learning effects. Finally, the study proposes countermeasures for teaching improvement from three aspects: teachers' teaching design, students' motivation and behavior, and optimization of e-learning platform content and function.