As higher education shifts from quantitative expansion to high-quality development, academic burnout among university students has become a widespread challenge, troubling university teaching management and talent cultivation. To explore the internal mechanisms among professional identity, subjective well-being, learning motivation, psychological capital, and academic burnout, this study targeted university students and conducted a questionnaire survey among 1,269 students from different majors and grades. Using AMOS software, a structural equation model was constructed to empirically analyze the pathways through which professional identity influences academic burnout via subjective well-being, as well as the mediating roles of learning motivation and psychological capital. The results indicate that: (1) Professional identity can reduce academic burnout by enhancing students’ subjective well-being; (2) Professional identity can strengthen students’ learning motivation through improving subjective well-being, thereby alleviating academic burnout; (3) Professional identity can enhance students’ psychological capital by improving subjective well-being, ultimately reducing academic burnout. Based on these findings, the paper proposes recommendations across four dimensions—student, faculty, family, and societal—to enhance professional identity and reduce academic burnout among college students.