Background: Infertility is defined as the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse. Hyperprolactinemia and thyroid dysfunction are associated with reproductive dysfunction and infertility. Hypothyroidism and hyperprolactinemia are found to be closely interrelated. This study aimed to observe the level of serum prolactin, free Tri-iodothyronine (fT3), free Thyroxine (fT4) and Thyroid stimulating hormone (TSH) in women with primary infertility and to correlate the level of serum prolactin with TSH. Methods: This study was conducted on patients visiting infertility OPD at the Institute of Medicine (IOM), Nepal from February 2016 to January 2017. Total 50 women with primary infertility were included in this study and 50 age-matched healthy controls were taken. Serum levels of prolactin, fT3, fT4, and TSH were measured in all subjects. Results: The mean age of participants was 26.8 years. The median serum prolactin (21.8) and TSH levels (4.5) were found to be significantly high in the case group (p<0.001). Out of the total subjects with hyperprolactinemia, 51.1% were found to have hypothyroidism. There was a moderately strong, positive and significant correlation between serum prolactin and TSH levels (r=0.62, p<0.05). ROC curve analysis showed that at a cutoff value of 22.5 ng/ mL for serum prolactin, a sensitivity of 86% and specificity of 82% could be achieved for detecting hypothyroidism. Conclusion: The high prevalence of hyperprolactinemia and thyroid disorders in primary infertility stresses the fact that all women coming for consultation due to infertility should be recommended to undergo thyroid function tests and prolactin estimation at early stages of infertility checkup.