Background: Glucose intolerance is an important contributor to the increased cardiovascular risk attributed to the metabolic syndrome, a constellation of cardiovascular risk factors that includes central obesity, dyslipidemia, hypertension, and disturbed glucose metabolism in patients with rheumatoid arthritis or systemic lupus erytheromatosus. Objective: To assess glucose intolerance percentage in rheumatoid arthritis and systemic lupus erythreromatosus patients. Patients and methods: The present study was a prospective study conducted on 90 subjects. The studied patients were recruited from Internal Medicine Clinic at Al-HusseinUniversityHospital during the period from January 2020 to January 2021. Patients were divided into three groups, group I: thirty patients with Systemic lupus erythromatosus (SLE), group II: thirty patients with Rheumatoid arthritis (RA) group III: included thirty healthy individuals as control group. The following laboratories were done for all groups to assess glucose intolerance (CBC, CRP, ESR, Fasting blood sugar(FBG),Post prandial blood sugar (PPBS), Haemoglobin A1C (HbA1C), Complement3 (C3), Complement4 (C4) and Albumin/creatnin (ALB/Creat ratio). Results: There were statistically significant difference between studied groups as regard blood glucose level assessment (FBS, PPBS & HbA1C), glucose intolerance, hemoglobin, ESR, Albumin/Creatinine ratio, complement 3, glucose intolerance and (FBS, PPBS & HbA1C) in SLE, glucose intolerance and (FBS, PPBS& HbA1C) in RA group, glucose intolerance and hemoglobin in SLE group however there were no statistically significant difference between studied groups as regard CRP, WBCs, PLTs and C4. Conclusion: SLE and RA patients appeared to have higher incidence of glucose intolerance than normal subjects.