We report a case of massive unilateral hydrothorax diagnosed at 18 weeks’ gestation in a fetus with normal karyotype. The fetus was affected severely by hydrops from 22 weeks. Initially, we performed a pleurodesis, but due to worsening hydrothorax evolving into hydrops, we proceeded with insertion of a trans-placental thoracoamniotic shunt. Improvement was evident from 1 week after the procedure followed by resolution of hydrothorax for the remainder of the pregnancy. After a cesarean delivery at 37 weeks, the neonate required prolonged neonatal intensive care unit stay. He was discharged when he was 2 months old and has remained stable until the present time.