〔Abstract〕 Objective To investigate the effects of luteinizing hormone（LH）levels on in vitro fertilization and em ‑ bryo transfer（IVF-ET）outcomes in an infertile population with normal ovarian reserve（NOR）undergoing con‑ trolled ovarian hyperstimulation（COH）with gonadotropin-releasing hormone antagonist protocol，and to explore the reasonable level intervals of LH during the follicular phase. Methods A retrospective analysis was conducted on 911 NOR infertility patients undergoing IVF-ET treated with gonadotropin-releasing hormone antagonist proto ‑ col. Patients were grouped based on baseline LH（bLH）levels，LH levels on the day of antagonist addition，and LH levels on the day of human chorionic gonadotropin（hCG）injection. According to bLH levels，patients were di‑ vided into Group A2（n=391）and Group B2（n=391）. Based on LH levels on the day of antagonist addition，pa‑ tients were divided into Group A3（n=600）and Group B3（n=311）. According to LH levels on the day of hCG in ‑ jection，patients were classified into Group A4（n=225），Group B4（n=227），Group C4（n=231），and Group D4 （n=228）. The clinical characteristics，COH outcomes，and pregnancy outcomes of patients in each group were compared. Results ① The bLH level could be used as a predictor of assisted reproduction outcomes in an infertile population with NOR，and going for assisted reproduction at bLH≥4. 51 IU/L was more favorable for the develop ‑ ment of pregnancy outcomes；② Addition of antagonist at LH≥5 IU/L on the day of antagonist addition improved pregnancy outcome ；③ On the day of hCG injection，there was no statistically significant difference in pregnancy outcomes among the four groups ；④ Analyses using generalized linear models revealed that basal follicle- stimulating hormone（bFSH）， basal estradiol（bE2）， Gn days，Gn volume and 2PN affected the number of good quality embryos. Conclusion In an infertile population with NOR using gonadotropin-releasing hormone antago‑ nist，bLH and gonadotropin-releasing hormone antagonist addition day LH levels may influence IVF outcomes. LH levels should be controlled at 5 IU/L and above on antagonist addition days，and bLH levels should be controlled at 4. 51 IU/L and above.