Stags striker Rhys Oates scored the only goal of the game after six minutes, capitalising on an error from Sunderland goalkeeper Lee Burge.
Lee Johnson made four substitutions at half-time, yet his side still struggled to create chances as their League Two opponents progressed to the next round.
It's the second year running that Mansfield have beaten Sunderland in the FA Cup after The Stags claimed a 1-0 win at the Stadium of Light last year.
The Black Cats won’t have another league game until November, 20 after their game against Lincoln was postponed due to international call-ups.
Sunderland’s next game will come in the Papa John’s Trophy against Bradford next week.
Our chief SAFC writer Phil Smith has delivered his verdict on how each player fared against Mansfield:
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1. Lee Burge - 4
His early error cost Sunderland dear, passing the ball straight to Oates who had the simplest of finishes. Didn’t have a great deal to do after that, though Mansfield had the better chances through the first half. 4 Photo: JPI Media
2. Frederik Alves - 5
Of the four half-time substitutions, this one felt the harshest by some distance. Perhaps could have shown a touch more drive in possession, which is perhaps why Winchetser was introduced, but was neat enough and did show for the ball. 5 Photo: JPI Media
3. Tom Flanagan - 5
Looked sluggish throughout the first half in a side that struggled to build any rhythm in possession. Mansefield found it too easy to break on the Black Cats, with Johnson making significant changes at the break. 5 Photo: JPI Media
4. Bailey Wright - 5
Played one or two dangerous passes in the second half that almost led to a threatening break. Distribution was erratic like many of his team-mates, and as a group they struggled to contain Mansfield in the first half. 5 Photo: JPI Media