Background: Oligohydramnios is a common problem in pregnancy that requires therapeutic measures in addition to managing the underlying cause. Objectives: This study aimed to assess sildenafil citrate’s impact on the amniotic fluid index in pregnant women with oligohydramnios and borderline oligohydramnios. Methods: Women with a singleton pregnancy, oligohydramnios, and gestational age of 24 to 36 weeks were included. Patients were randomly divided into two groups. The intervention group also received 50 mg of sildenafil citrate every 8 hours and 3 liters of isotonic solution per day. In the control group, a placebo was given along with hydration therapy, similar to the intervention groups. The amount of amniotic fluid was reassessed one week and two weeks after treatment. Weekly measurements of amniotic fluid volume, biophysical profile, and non-stress test were used twice a week for fetal monitoring. This study analyzed the data using SPSS version 23 with a significance threshold of P ≤ 0.05. Results: Finally, there was a substantial change in the amniotic fluid level between the basic and end of the second week (P ≤ 0.05). There was no apparent distinction between the two groups regarding pharmaceutical side effects or the consequences of pregnancy. Conclusions: Sildenafil citrate enhanced amniotic fluid production, although no significant issues were seen for the mother or fetus.