The Edinburgh-based firm said the signing of the exploration authorisation by the president of Cameroon gives it and its joint venture partners in the Etinde development exploitation rights for an initial period of 20 years, with the option to renew for up to a further 10 years.
Chief executive Kevin Hart said: “The award is a significant milestone and enables the progression of the exciting development plans on Etinde.
“This is an important project for Cameroon and we are pleased to be able to support the country in its aim to further develop its hydrocarbon resources.”
Bowleven last month announced plans to raise about $250 million (£148.6m) by selling a 50 per cent stake in the project to Russian energy giant Lukoil and African firm NewAge.
Shares in Aim-quoted Bowleven rose as much as 4.4 per cent in early trading after the exploration authorisation was announced.