Dissertation (MMED Obstetrics and Gynecology)Preeclampsia is a common medical condition in pregnancy with a prevalence of 6-10%. Hematological derangements are common in Preeclampsia as a complication and can lead into bad obstetric outcomes. This study has investigated the hematological indices changes and the associated obstetric outcome at a Referral Hospital. The study aimed to assess the Hematological Indices and obstetric outcomes among pregnant women with preeclampsia at Iringa Regional Referral Hospital. The study was Hospital based cross-section study with the sample size of 215 pregnant women with preeclampsia in their 3rd trimester. The sampling method was convenient and involved all pregnant women with preeclampsia in their 3rdtrimester during the study duration. Data were collected using pretested questionnaire, and the venous blood samples were collected on ante cubital vein for hematological analysis by SysmexXP300machine. Data was analyzed by using SPSS version 25. During the study there were 215participantsamong them 179had deranged hematological indices. Those with low platelets count 44.65%, low hemoglobin, 60.47%, raised PCV was 35.81% .high MCV was29.77% and low MCHC was 4.65%..Adverse maternal outcomes were significantly associated with low platelets PCV , and MCV ). The adverse fetal outcomes were also significantly associated with low hemoglobin levels. During this study, it was found that hematological indices in Preeclampsia are a common complication and are associated with adverse obstetric outcomes.