Rationale & Purpose: Teacher career development theory indicates that the development priorities of teachers throughout their careers vary. The dynamic process of teachers’ career development evolves with their increasing seniority, accumulation of teaching experience, and mental maturation. The present study tracked student teachers for approximately 2 years after graduation to gain insight into the development of their creative teaching beliefs and the creative teaching process as a whole. This study analyzed the longitudinal development of student teachers’ beliefs on creative teaching during the student, student teacher intern, and first-year teacher stages of their careers. This study investigated the seldom-explored relationships between student teacher interns and their supervisors. In addition, this study analyzed the influence of consistent interactions between student teacher interns and their supervisors on the advancement of the student teachers’ creative teaching beliefs. Furthermore, because the establishment and promotion of a professional learning community may crucially influence the development of creative teaching beliefs in first-year teachers, this study evaluated the influence of professional learning communities on the growth of new teachers’ creative teaching beliefs. Student teachers’ willingness to teach at different career stages affects the time that they are willing to spend preparing for their certification and examinations; such teachers’ creative teaching beliefs may vary at different stages. This study regarded teaching willingness as a covariate that changes over time. Finally, this study investigated the influence of teaching willingness on the growth rate of creative teaching beliefs at various stages of student teachers’ careers. Methods: This study employed longitudinal survey data to track the growth trajectory of teachers’ creative teaching beliefs from their time as students until 2 years after graduation. In addition, this study explored the covariation in teaching intentions over time, the interactions between student teacher interns and their supervisors, and the influence of congruent participation in professional learning communities on the growth trend of creative teaching beliefs. This study lasted for 3 years and included the implementation of six surveys. Four research tools were employed: a creative teaching beliefs scale, a teaching willingness scale, a teacher professional learning community scale, and a student teacher intern–supervisor interaction consistency scale. The results for all scales indicated that they had good reliability and validity. The study participants were teachers with 2 years of postgraduate teaching experience. This study identified 281 students, who were followed for 3 years; the final sample comprised 98 teachers who participated in the study for 2 years after graduation. This study implemented hierarchical linear model analysis. The first explanatory variable was time, whereas willingness to teach was the covariate that changed over time. The second-level explanatory variables included sex, the method used to study education, examination scores , the degree of interaction between the student teachers and the internship instructors, the extent to which the school invested in teachers, whether the school had established a professional learning community, participation in the professional learning community, and current work status. Results/Findings: The results of this study reveal the following: first, student teachers expressed their creative teaching beliefs through three dimensions, namely enhancing creativity intention, creative cognition and attitudes, and creative teaching material and activity design. These three dimensions exhibited downward linear trends. Second, consistent interaction with a supervisor exerted a negative moderating effect on the rate of decline of creative teaching beliefs. Third, different configurations of professional learning communities influenced the downward trend of creative teaching beliefs. Fourth, a positive covariance was present between the willingness to teach and the growth of creative teaching beliefs. Conclusions/Implications: In terms of theoretical contributions, the study results indicate a downward trend in the creative teaching beliefs of student teachers; these results are consistent regardless of the dimension through which teachers expressed their creative teaching beliefs. Although the results of the present study were unexpected, they merit attention. Student teachers generally develop creative teaching beliefs after 4 years of university education; some scholars believe that student teachers should have a high degree of creative teaching beliefs. However, the survey results of the present study indicate that student teachers may face graduation pressure in their senior year. Moreover, they may begin to experience feelings of ambivalence toward their future teaching careers, leading to a decline in creative teaching beliefs. With respect to their internships, students are likely to encounter a gap between theory and practice or a conceptual gap between their own ideas and those of their supervisors, which may also lead to a decline in creative teaching beliefs. After completing an internship, the combined pressure of preparing for examinations, applying for jobs, teaching in a new school, and adapting to a new environment may contribute to a decline in creative teaching beliefs. Furthermore, in terms of first-level covariates, the results demonstrate that teaching intention was positively associated with creative teaching beliefs. However, the results also indicate that creative teaching beliefs exhibited a downward trend; therefore, the willingness to teach may also exhibit a downward trend. The results of this study reveal that student teachers may not only gradually lose their belief in creative teaching over time but may also experience a decreased willingness to teach. This trend merits further attention from educational scholars. Finally, this study identified factors that may counteract these downward trends. The factors that helped reduce the decline in willingness to teach included consistent interaction with supervisors during internships, participation in professional learning communities, cooperative learning, shared leadership, and shared teaching in professional learning communities. These factors being present in a greater magnitude was associated with a slower rate of decline in creative teaching beliefs. This finding demonstrates that professional learning communities are crucial for teachers and justifies their promotion by the Ministry of Education. Schools should focus on encouraging teachers to participate in professional learning communities. The present study presents the following recommendations: 1) the creative teaching beliefs of teachers and students should be strengthened through teacher training courses, and appropriate supervisors should be carefully selected to reduce the decline in creative teaching beliefs; 2) the creative teaching beliefs of new teachers should be strengthened through teacher screening and an assessment of their willingness to teach; and 3) professional learning communities should be promoted.