Congenital idiopathic pleural effusion is a very rare condition in neonates. Majority of the congenital pleural effusion are associated with documented cause such as hydrops fetalis, chromosomal causes, cardiac or pulmonary causes. The congenital effusion is mostly transudate, exudates or chylous. Hemorrhagic pleural effusion without any documented coagulation abnormality is rare. We are reporting a case of unilateral hemorrhagic pleural effusion in a preterm neonate.