Miglioranzi opened the scoring for Swindon after only 7 minutes with a close range shot that went in off the post.
In the first half Swindon had fairly few chances, and it was Wycombe who were having most of the play with Evans having to make some good saves, and O'Hanlon having to clear the ball away.
In the second half Swindon started a lot better, and had much more of the ball.
In the 52 minute Sam Parkin scored his 22 goal of the season to make it 2-0 after a mistake by the Wycombe defence allowed Parkin to run in from 40 yards with only the 'keeper to beat, which he managed.
Rory Fallon should have scored in the second half, but some how he couldn't get the ball into the back of the net.
On 74 minutes Swindon were given a penalty after a hand ball in the area. Andy Gurney took the kick and made sure of all three points by making it 3-0.
Adi Viveash played his first game for Swindon in six months when he came on to replace Sean O'Hanlon.
Overall a very important win for Swindon after all the top three failed to win, Swwindon can still finish in 2nd if they will their last three games, and QPR and Bristol City slip up.
Swindon's next game is at home to Oldham next Saturday at the County Ground.