The aim of the present study was to examine the effects of preeclampsia on posterior ocular blood flow through optic coherence tomography angiography (OCTA). The study included preeclamptic pregnant women (group PPW), healthy pregnant women (group HPW) and control non-pregnant women (group CNPW). The blood flow area of retina, optic nerve head and choriocapillaris were assessed through OCTA. Retinal superficial blood flow area (RSBFA) was similar in group PPW, HPW and CNPW (p = 0.101); likewise, there was not any difference in retinal superficial parafoveal vessel density (RSPFD) between the groups (p = 0.685). There was not any difference detected in retinal deep blood flow area (RDBFA) in group PPW, HPW and CNPW), likewise retinal deep parafoveal vessel density (RDPFD) was found similar between the groups (p = 0.184). The choriocapillaris blood flow area (CBFA) was different between the groups (p = 0.000) and less in the group PPW than in group HPW. The CBFA was 1.875 ± 0.05 mm2 in group the PPW, 1.928 ± 0.05 mm2 in the group HPW and 1.464 ± 0.06 mm2 in the group CNPW. Similarly, the optic nerve head blood flow area was lower in the group PPW compared to the group HPW (1.567 ± 0.38 mm2, 1.690 ± 0.20 mm2 and 1.592 ± 0.25 mm2 in the group PPW, group HPW and group CNPW respectively; p = 0.002). Posterior segment ocular blood flow may be diminished in preeclamptic women. OCTA may enable to monitor ocular blood flow dynamics and give important clues in the diagnosis of retinal vascular pathologies accompanied by systemic diseases.