Chairboys manager John Gorman said it was their worst performance of the season.
Wrexham showed what was on the cards when Juan Ugarte controlled a left-wing cross from Matt Crowell and shot narrowly wide.
The first goal came when Crowell drove a corner into the box where the towering centre-half Dennis Lawrence got up to head past Matt Duke.
It all came from Mike Williamson trying to shepherd out a long throw from Andy Holt.
Youngster Aam Williams, on loan from Aston Villa headed the second goal in classic style from a Crowell cross, after the lively Ugarte made the early running on the right flank.
Wycombe came under more pressure and Duke had to be at his best diving to turn Ugarte's snap-shot away round the post.
Again when Holt crossed, Roger Johnson hacked off the line to deny the enterprising young Williams, who looked certain to get his second goal.
Wrexham had another chance when Holt set up Levi Mackin who pulled the ball back to find the unmarked Simon Spender, but he wasted his chance when missing the target from barely eight yards.
Wycombe produced very little danger for the Wrexham defence. Top marksman Tommy Mooney had a 30-yard speculative shot saved before trying a cheeky chip that beat keeper Mike Ingham but was off target.
Jermaine Easter also missed when Russell Martin set him up with a right-wing cross, before Clint Easton shot wide of the far post from a Stefan Oakes pass.
Wycombe changed tactics, bringing on Dean Bowditch as a third striker to play behind the front two.
It made little difference and they had few chances. Matt Bloomfield was nearest to scoring, shooting over the crossbar from the loose ball after Wrexham's Jim Whitley blocked a shot from Johnson.