Pregnancy is a natural physiological variation as a result of hormonal and metabolic changes. Worldwide a large proportion of women are expected to die each year as a result of pregnancy complication related to hematological profile alterations. Therefore, this study is aimed at assessing hematological indices of pregnant in comparison with non-pregnant women.A comparative cross-sectional study was conducted among pregnant and non-pregnant women at the University of Gondar Hospital, from February to April 2015. A blood sample was collected from 139 pregnant and 139 age-matched non-pregnant women using systematic random sampling technique. Data analysis was made using SPSS version 20. Level of significance was analyzed using independent t-test and Mann-Whitney U test. A p-value ≤ 0.05 was considered statistically significant.In this study, pregnant women had significantly higher WBC count [(7.08 ± 2.07 vs. 5.77 ± 1.85) x 109/L], MCV [(93.16 ± 3.44 vs. 90.74 ± 4.12) fL], MCHC [(30.40 ± 1.19 vs. 29.47 ± 1.46) pg], Neutrophil count [(4.73 ± 1.86 vs. 3.06 ± 1.47) x 109/L], Lymphocyte count [(1.65 ± 0.41 vs. 1.2 ± 0.54) x 109/L], RDW [(49.35 ± 2.9 vs. 46.37 ± 2.73) fL], PDW [(14.02 ± 0.6 vs. 13.12 ± 0.19) fL], and MPV [(10.49 ± 0.95 vs. 10.06 ± 1.18) fL] compared with controls. The RBC count [(4.55 ± 0.38 vs. 5.14 ± 0.53) x 1012/L], Hb [(13.73 ± 0.96 vs. 15.30 ± 1.074) g/dL], Hct [(42.14 ± 2.55 vs. 47.16 ± 3.36)%], and Platelets [(196.07 ± 48.88 vs. 249.36 ± 62.73) x 109/L] were significantly lower among pregnant women compared to the control group, respectively. This study also indicated that there was a significant difference in MCV, MCH, platelet count, absolute lymphocyte count and RDW across the three trimes-ters of pregnancy.This study found a statistically significant difference in the majority of hematological indices between pregnant and non-pregnant women. Trimesters of pregnancy have an influence on some hematological indices. This study provides baseline data for basic hematological indices changes, and it is vital especially in the antenatal care assessment to avoid pregnancy-related adverse outcomes.