Currently, Japanese language courses in some colleges and universities are still based on didactic teaching, with a lack of interaction between teachers and students, which makes it challenging to meet the needs of students’ communicative ability development. This paper constructs a blended teaching model of the Japanese language in colleges and universities based on the SPOC teaching platform, selects two Japanese language parallel classes in the second year of a university in H city as the research object, and designs the relevant teaching process. Based on the students’ learning data in the SPOC teaching platform, the learners’ behavioral characteristics are analyzed. The K-Means algorithm is improved to obtain the optimal clustering center by using the density weights, and the learning characteristics are clustered. Then, the effectiveness of the SPOC teaching model was responded to by the teaching effect of students’ Japanese speaking and reading skills. In addition, the correlation between learner behavioral characteristics was analyzed using Pearson’s correlation coefficient. It was found that SPOC-based Japanese language teaching increased students’ willingness to learn independently by 5% to 31%, and students’ Japanese reading posttest scores in the experimental group increased by 5.123 points compared with the control group, and online learning behaviors showed a high degree of correlation with learning achievements. The application of the SPOC teaching mode in Japanese language teaching can effectively enhance students’ learning engagement, promote the enhancement of students’ intercultural communication skills, and provide a new path to improve the quality of Japanese language teaching.