The world number 31 Fernandez pulled away after breaking early in the opening set, but Gibson refused to fade, twice clawing back from a break down to stay level. Fernandez, 24, steadied herself in the closing stages and converted her first set point to take the opener 7-5.
Fernandez then dominated the second set, racing into a double-break lead as Gibson's challenge faded. The Canadian eventually wrapped up a commanding 6-0 set to seal the title.
Gibson, who advanced to her first WTA final after her semi-final opponent Tatiana Prozorova was forced to withdraw, missed out on claiming her maiden title.