The study aimed to evaluate Glucagon-Like Peptide-1 levels in Polycystic ovary syndrome (PCOS) infertile female with Diabetes Mellitus (DM) and compare the results with control group, also, to find the correlation for GLP-1 with Luteinizing hormone (LH), Follicle stimulating hormone (FSH) and LH/FSH ratio that may be used in prediction atherosclerosis in these patients. The study included nineteen women with age ranged (30-40) years and BMI ranged between (30-35) Kg/m 2. Subjects were divided into two groups: group (1) consist of (45) females as a healthy control and group (2) consist of (45) infertile females with PCOS and DM as complication. Fasting serum glucose was determined by using commercial kits (Biolabo SA-France); LH, FSH, prolactin were determined by ELISA, fasting serum insulin was determined by using ELISA kit (DRG-Germany). Insulin-resistance (IR) calculated by (HOMA-IR). FSH, LH, LH/FSH ratio and prolactin levels for all studied groups were measured. A highly significant elevation in prolactin, LH and LH/FSH ratio was found when G1 comparing with G2. While significant reduction seen in FSH levels in G2 comparing to G1. A high significant elevation in Fasting blood glucose,% HbA1C levels in patients group when comparing to healthy control. Results revealed a highly significant elevation in insulin, HOMA-IR and glucagon, while there are a significant reduction in GLP-1levels. There is significant positive correlation was found in GLP-1 levels with (FSH) in G1, while a significant negative correlation was observed in levels of GLP-1 and (FSH) inG2. A significant negative correlation was found in GLP-1 levels