In a statement, Petronas said the offshore block was located in southern Gabon and measures an approximate 2,500 square km surface area in water depth ranging from 2,000 metres to 3,000 metres.
Petronas would operate the block with an 80% interest while the Government of Gabon owned the remaining 20% interest.
The signing of the PSC took place at the Arambo Building, Libreville.
"The signing marked an important milestone as Petronas is re-entering the Republic of Gabon, now focusing on the deep water pre-salt play," said Petronas Vice-President of Exploration International Effendy Cheng Abdullah.