With second spot on the table already assured, coach Bryan Redpath made 12 changes to his starting line-up, but Carnegie were still too strong for the third-placed Londoners.
The two sides will now meet in a two-legged play-off, with Yorkshire travelling south for the opener on April 28.
Richard Beck and James Thraves scored close-range tries for Yorkshire - both converted by Warren Seals - either side of an Aaron Penberthy penalty goal for the visitors.
But Ealing, who had Chris York sin-binned before Yorkshire’s first touchdown, spent the final minutes of the first half camped close to Carnegie’s line and a penalty try was awarded after a series of offences by the hosts, Penberthy adding the extras.
Yorkshire regained control of the game just four minutes into the second half when Matt Beesley drove over for an unconverted try to make it 19-10.
Penberthy landed a penalty for Ealing, but Yorkshire responded with a quality try for Andy Forsyth, created by Steve McColl and Chris Elder.
Seals tagged on the two to make it 26-13 and added another conversion after Mike Mayhew scored following a strong run by Mike Myerscough.
Willie Ryan pulled a try back for Ealing, but Penberthy’s conversion with seven minutes left completed the scoring.