Introduction: Pregnancy in women with diabetes mellitus is associated with an increased risk of congenital malformations, obstetric complications and neonatal morbidity. Aim of the work: The current study was aimed to assess the effect of different types of diabetes mellitus without vascular changes on maternal and fetal outcomes. Patients and methods: This was a cross sectional study done at zagazig university hospital and included 50 cases of gestational and pregestational diabetic pregnant women in third trimester of pregnancy (28wks to 40wks) attending at Zagazig University hospitals in the period from March until September 2019. Patients divided into 2 groups: Group I: included 25 pregnant women with pregestational diabetes mellitus (Type 1and Type 2 DM) without vascular changes, Group II: included 25 pregnant women with gestational diabetes mellitus. Fasting &2 h postprandial blood glucose level, HbA1c, Complete general and abdominal examination, Obstetric Ultrasonography was done for all patients. Results: There was no statistical significant difference in positive family history of diabetes and previous history of congenital fetal malformation, Intra Uterine Fetal Death and gestational diabetes mellitus between the studied groups. There was no statistical significant difference in gestational age at delivery and mode of delivery between the two groups. Conclusion: We concluded that either diabetes was gestational or pregestational there was no statistical difference between maternal and fetal outcomes. Optimal control of blood glucose resulted in lower neonatal and maternal complications. Further studies on large geographical scale and larger sample size are required to support our conclusion.