After a miserable first half, the Swans took the lead in the 50th minute when Leon Britton played in Paul Connor for his 11th goal of the season.
The former Rochdale striker eluded a couple of tackles before side-footing past keeper Frank Talia.
Nine minutes later they doubled their advantage when Lee Trundle went on a mazy run into the area before being brought down by Talia.
Trundle dusted himself down before blasting the spot kick to the keeper's left.
Connor and substitute Brad Maylett both had chances of putting the game beyond the visitors, but the home defence switched off and it was Wycombe who ended the game on the front foot .
Roger Johnson pulled a goal back in the 77th minute when the Swans rearguard stood motionless as a cross came in.
Then seven minutes from time a Steve Guppy free-kick received the slightest of touches from former Swansea loan player Nathan Tyson and the scores were back level.
Alan Tate had replaced the suspended Adrian Forbes in a defensive-minded Swansea midfield, while Wycombe gave a debut to veteran striker Steve Claridge and had former England cap Guppy playing on the left side of midfield.
After a dire opening period, Swans boss Kenny Jackett was forced to make changes and he took off skipper Andrew Gurney together with Andy Robinson, switched Britton to central midfield and brought on Maylett and Ijah Anderson.
The changes had an immediate effect with Britton prominent right from the start and once they had taken a two goal lead, there appeared to be only one outcome.