Mr. Foday Gassama whose appointment came into effect on Monday succeeds Ya Kumba Jaiteh who was fired by Mr. Barrow late last month.
Gassama’s appointment comes before the furor caused by Ms. Jaiteh’s dispatch had died down.
A statement from President Barrow’s office said the Gambian leader was acting under section 88 1(b) of the 1997 constitution to nominate Mr. Gassama.
The Gambian National Assembly has been riding a tempestuous storm of controversy triggered by the sacking last week of his predecessor Ms. Jaiteh through the head of the civil service.
Members of the august House have been divided over the constitutionality or otherwise of her removal, which prompted 31 MPs from across the political divide to rally behind her.