Samira Suleiman opened the scoring in the 26th minute with a supersonic header from a Portia Boakye corner kick.
Portia Boakye added the second six minutes later with a thunderous strike from 25 yards.
On the stroke of half time, Samira Suleiman was gifted with the ball from the Tunisian goalie but shot wide at the yawning net.
Samira came close again on the 69th minute but her shot missed the post by inches.
Priscilla Adobea made it three with a solo effort after she swiftly moved past the Tunisian right back, dribbled the center backs and nutmegged the goalie with ten minutes to end proceedings.
Samira added the fourth with a superb volley with a minute to end proceedings.
The win means Ghana has qualified on a 6-1 aggregate for the championship to be hosted in Cameroon later this year.