The Northern Combination newcomers had defeated the Owls 3-1 but a goal from debutant Shelley James was enough to net the points last night.
An exquisit 77th minute chip from James left the visitor's keeper sinking to her knees in despair, as Sheffield FC suffered their first defeat of the season.
It was Wednesday's first win, which lifted them to fifth place in 
the table, while Sheffield FC slip to third.
The Owls are away to Middlesbrough on Sunday, while Sheffield FC host Wakefield.
But first there's a Friday fixture between Tranmere Rovers and Mossley Hill, kick-off 7pm at Ashville FC.
