The former Gllingham boss returns to National League football following a four-month absence, having left the Director of Football role at Ebbsfleet United in August.
The Wings were defeated by high-flying St Albans City last night, continuing a run of form which has seen the side drop to bottom of Vanarama National League South.
Quinton leaves Park View Road after one year in the home dugout.
A statement said: "The Club can announce that, following Tuesday evening’s defeat to St. Albans City, Brad Quinton and his management team have been relieved of their duties.
"The Wings lay at the foot of the table after a run of one win in 11 games in what has been a stop-start season.
"We would like to place on record our thanks to Brad Quinton & his management team for all their efforts during their time at the Club during unprecedented circumstances. We’re sure supporters will join the Directors, Players and Staff in wishing Brad and his team all the best for the future."
PHOTO: Welling United FC