The learner-centered teaching concept and the flipped classroom teaching method are effectively combined to become an important mode for today’s mixed teaching reform. The “rain classroom” has provided an effective platform for the combination of the two. First of all, we use the “rain classroom” teaching platform and take a course as an example to study the learner-centered flipped classroom teaching reform design. The main teaching methods are grading of ability level, after-school study group, case study, and online and classroom interactive Q&A. Secondly, through the investigation of students’ learning ability and willingness to learn, the teaching framework is designed to be suitable for students to learn and for teachers to teach students according to their aptitude. Finally, by paying attention to the real-time feedback of the effect of students using the flipped classroom, this paper proposes problems that should be paid attention to when implementing the flipped classroom. The results show that the course has been successful after its setup and implementation. The learnercentered teaching method, which respects the ability level classification of learning initiative, can complement the after-class content with the classroom content, and effectively improve the teaching and learning effects.