A late goal from Charlie Adam secured maximum points for Mark Hughes' men after Stephane Sessegnon had equalised Gareth McAuley's own goal
The game looked to be heading for a draw after Stephane Sessegnon's strike in the second half cancelled out an own goal from Gareth McAuley after 22 minutes.
However, a fine run and shot from Adam ensured a win for Mark Hughes' men, while the Baggies will play another season in the top flight following Norwich's relegation.
The result caps off a good campaign for Mark Hughes' men, who have secured a first top-10 finish in the Premier League and surpassed the 47-point haul they recorded in 2010.
Despite knowing that only a mathematical improbability would see West Brom relegated, head coach Pepe Mel insisted that this game represented his side's "biggest test" of the season.
And the hosts looked to have a spring in their step in the opening exchanges, nearly taking the lead inside three minutes when a frantic goalmouth scramble saw the ball fall to Sessegnon, who cannoned an effort off the underside of the crossbar from two yards out.
However, Stoke, who arrived with a 100 per cent Premier League record at The Hawthorns, responded well and almost took the lead six minutes later when Jonathan Walters raced away from the defence, before stinging the palms of Ben Foster with a well-struck drive.
The Republic of Ireland forward was at the centre of proceedings again within two minutes, somehow contriving to head wide from six yards after some great work down the right from Geoff Cameron.
But the visitors were rewarded for their efforts when a neat one-two inside the area allowed Marko Arnautovic to break free of his man before fizzing a low ball across goal that was turned in by a despairing McAuley.
West Brom struggled to find any sort of rhythm in the opening half, but were level 11 minutes after the break.
>A sweeping counterattack ended with Craig Dawson crossing from the right for Sessegnon to apply a calm finish.
The hosts were nearly guilty of undoing their good work immediately, as Arnautovic got away a curling shot that narrowly failed to find the target.
Yet West Brom continued to press, with Sessegnon heading straight at Thomas Sorensen and Mulumbu clattering the post a minute later.
It looked as though both teams would be content to settle for a point, but Adam then struck with a powerful effort from the edge of the box, ensuring Stoke leapfrogged Newcastle United into ninth spot.