The Spaniard's strike midway through the second half was enough to earn all three points for the Potters and subject the Foxes to another defeat at the King Power Stadium.
Bojan Krkic scored the only goal of the game in the 63rd minute, following a period of pressure from Mark Hughes' men, who in truth spent the large part of the game on the back foot.
Leicester had the better of the first half, but Stoke emerged after the break with added belief and adventure about its play and got its reward in the form of a fourth away league win of the season.
Nigel Pearson named Leicester's record signing Andrej Kramaric among his substitutes, following the completion of the Croatian's move from HNK Rijeka. The striker was waiting to come on when the crucial goal was scored, and he could not prevent Leicester slipping to a first defeat in five, which leaves the club three points from safety.
Shorn of captain Ryan Shawcross to injury, Stoke was cautious out the blocks as Leicester dominated possession, though chances were ever-present on the counter for the visitors.
Only a last-ditch Danny Simpson challenge stopped Victor Moses from tapping home the opener. But Leicester's dominance of the ball began to tell as the half drew on.
Jeffrey Schlupp showed no ill effects of the injury concerns that forced him from Ghana's Africa Cup of Nations squad, creating good opportunities for Anthony Knockaert and Jamie Vardy — but neither could beat Asmir Begovic in the Stoke goal, who also saw a curling David Nugent effort drift just over.
For all its good work at the end of the first half, Leicester could have been behind within 60 seconds of the restart. A clever ball from Moses, in behind Paul Konchesky, put Marko Arnautovic in on goal. But the Austrian lashed at his shot and only hit the side-netting from close range.
Steven N'Zonzi struck the target with a stinging volley 10 minutes later but Ben Hamer was equal to it.
Pearson did look to Kramaric, but before the Croatian could be introduced, Stoke took the lead.
Buoyed by their strong start to the half, the visitors looked more dangerous with every foray forward. And Bojan broke the deadlock by collecting a Walters pass, turning and firing into the bottom corner in one swift motion.
There were encouraging signs from Kramaric in the closing stages as he held the ball up well and brought others into play, but his debut — and Leicester's performance — was devoid of that final touch in front of goal.