Introduction: Ovarian follicle development requires tight coordination between several factors to initiate folliculogenesis to develop a mature and fertile egg. Research has proven that cell cycle factors might lead to follicle development, hover specific understanding on individual CDKs and follicle activation is not investigated. Among cell cycle regulators, CDK6 is really a key player through binding to cyclin D resulting DNA synthesis and genome duplication. Interestingly, the CDK6 gene is differentially expressed in oocytes and granulosa cells from human primordial and first follicles, which advise a potential role of CDK6 within the primordial-to-primary transition. Within this study, we investigated the possibility regulatory role of CDK6 in advancement of primordial to primary follicle transition using BSJ-03-123 (BSJ), a CDK6-specific degrader. Methods: In mouse ovarian in vitro culture, BSJ reduced the activation of primordial follicles, and reduced follicle development. Like a next thing, we examined the egg maturation read-out and located that BSJ-treated follicles matured to competent MII eggs with resumption of first meiosis, comparable using the control group. Results: Significant, it seems that inhibition of CDK6 did increase quantity of apotoptic cells, articular within the granulosa cells, but didn’t have effect on ROS degree of cultured ovaries when compared with control group, indicating the cells weren’t stressed. Oocyte quality thus made an appearance safe. Discussion: The outcomes of the study indicate that CDK6 plays a part in the primordial-to-primary transition, suggesting that cell cycle regulation is a valuable part of ovarian follicle development.