ABSTRACT In this article we present a case of Acute unilateral Proptosis with sudden, painful loss of vision following right eye trauma with tennis ball while playing cricket. The patient developed right eye retrobulbar haemorrhage along with subperiosteal hematoma but even after severe high intraocular pressure compressing the optic nerve had a complete visual recovery following orbital decompression surgery. We have tried to emphasis on the point of importance of surgical intervention in providing good visual recovery in severe tensed post-traumatic proptosis. Keyword: Unilateral post-traumatic proptosis, retrobulbar haemorrhage, subperiosteal haemorrhage, orbital decompression, anterior orbitotomy, lateral canthotomy with cantholysis.