This Random cross sectional study was conducted to evaluate the effect of Inhibin B in Infertiled women in Kirkuk city which is one indicator to the reproductive ability in polycystic ovary patients ,consider as the disease common in Infertility, also to study the changes in reproductive hormones Follicular stimulating hormone(FSH), Luteinizing hormone (LH) , Estrogen(E2) , prolactin(PRL) Testosterone, Samples were classified into two groups: (38) blood samples from women with primary infertility ,(29) blood samples from women with secondary infertility , compared with (18) samples from women as control group. Blood samples were taken within 2-4 days of menstrual. period of women with their ages ranged from 17-46 years who were visiting the infertility unit in Azady teaching hospital in Kirkuk city. Infertile Samples were divided into two groups: infertiled women with polycystic ovary syndrome and infertiled women for other reasons . the ratio of polycystic ovary syndrome of primary infertility was 65.78% while of secondary was 58.62%. Results indicated that there was a high significant increase in Inhibin B level (p<0.05) in secondary infertiled group compared with both control group ,and primary infertiled group and also a significanl increase in Prolactin level (P< 0.05) of both primary and secondary infertiled group compare with control group. and a high significant increase in Inhibin B level (p<0.05) in secondary infertiled group of (G1) polycystic ovary syndrome and (G2) infertiled women for other reasons compare with primary infertiled group and also high significant increase in FSH level for (G2) in secondary infertiled group. The relation between levels of inhibin B and body mass index was studied which indicated the high level of inhibin B (141.14± 55.51) pgml) in obese infertiled women.