She became a controversial figure after telling The Guardian newspaper that Jammeh would be prosecuted for crimes committed by his regime
Fatoumata Jallow-Tambajang is often described as the woman who persuaded The Gambia's divided opposition parties to club together and field a single candidate in the December 1 election which Barrow eventually won.
A former health minister in the early years of ex-leader Jammeh's 22-year rule, Jallow-Tambajang was specifically chosen to correct the gender balance in Barrow's administration, spokesman Halifa Sallah told journalists in announcing her appointment.
"Consideration has been given in terms of balance of the constitution of the cabinet," he said.
She has become a controversial figure in recent weeks after telling The Guardian newspaper that Jammeh would be prosecuted for crimes committed by his regime, an act almost immediately followed by the mercurial president announcing he no longer recognised the election result.
A development expert who previously worked of the United Nations, Jallow-Tambajang has also argued that a national commission for asset recovery should be established.
This would be particularly pertinent given claims by Barrow's team that Jammeh stole $11 million and several luxury vehicles before departing for Equatorial Guinea.
Jammeh also had a female vice-president, Isatou Njie-Saidy, who stayed loyal to him for several years in an administration where defections and unexplained firings were common.