Obesity is a health problem that increases worldwide and can cause metabolic complications. Gynecological problems such as menstrual cycle disorders, polycystic ovarian syndrome and infertility are more common in obese women. Infertility is defined as failure to achieve pregnancy at the end of a year despite regular unprotected sexual intercourse. Insulin resistance seen in obesity may adversely affect the hypothalamic-pituitary-ovarian axis, causing anovulation and infertility. It also negatively affects oocyte quality and endometrial receptivity. Obesity also adversely affects treatment results for infertility. Treatment for obesity has been shown to increase infertility treatment success. In conclusion, when evaluating infertile patients, obesity should be considered as an important factor that may affect the etiological and treatment success.