Through a survey of faculty members from 21 top research universities in China, this study analyzes the impact of the tenure reform on faculty members' job insecurity and innovative work behavior in research. The results indicate a negative relationship between the tenure-track system and faculty's innovative work behavior in terms of trying new directions and methods. However, no significant impact of the tenure track on the implementation and support of innovative ideas was observed. This study also reveals that the tenure track increased job insecurity among faculty members, primarily quantitative insecurity. This is due to higher publication demands and the strict enforcement of the "up-or-out" contracts, which resulted in rising concerns over job loss. Further analysis reveals that job insecurity played a mediating role in the relationship between the tenure track and faculty members' innovative behaviors in academic research. Based on the findings, this study recommends raising the criteria for tenure-track admission to reduce excessive peer competition. It also highlights the need to enhance academic autonomy and peer evaluation to ensure the quality of research outputs. In addition, it suggests implementing a more flexible exit mechanism to reduce job insecurity for faculty on the tenure track, thereby creating a more stable environment conducive to research innovation.