Fichardt, who came into the final round with a five-stroke advantage over Simon Wakefield, set the tournament record at 5-under 279 at Aa Saint Omer Golf Club despite his rough final round.
The South African claimed his first European Tour victory since the 2003 Qatar Masters and third career title overall.
Wakefield made Fichardt's job easier by turning in a subpar performance himself, posting a 1-over 72 to end up alone in third place at minus-1.
Gary Lockerbie (69) filled the void by firing a 2-under 69, claiming sole possession of second at 2-under.
Sharing fourth at 2-over 286 were Charlie Ford (70), Adam Gee (72), Pelle Edberg (72) and Wil Besseling (73).