The three points lifted Micky Mellon's in-form outfit into the National League play-off places.
Fondop notched the decisive goal four minutes before half-time, smashing a shot high into the roof of the net after Dorking failed to clear a corner.
The goal came as reward for Latics' dominance of the first half, but Dorking threatened an equaliser after the break.
The best chance came just after the hour when Latics goalkeeper Mathew Hudson made an outstanding double save to deny Jason Prior and Seb Bowerman.
Latics, who are now sixth in the table thanks to this fifth straight away win, are back in action on Saturday when they host Hendon in an FA Trophy fourth round tie.
