The winger, who joined the Potters initially on a loan deal from Real Zaragoza in 2010, was due to leave the club at the end of the 2012/13 season.
But Pennant has impressed new boss Mark Hughes who believes the 30-year-old can prove an attacking asset for next term.
"I've admired Jermaine from afar and there is no question about his ability," said Hughes.
"I am looking to introduce more creativity and attacking options to the side, qualities Jermaine can certainly offer us.
"I had a very positive meeting with him and it's now up to him to show everyone what he is capable of doing."
Chief executive Tony Scholes said: "We have been impressed with Jermaine's determination to prove any doubters wrong.
"He clearly had a difficult time last season, but the Stoke fans love him and he loves them. We believe that at 30 years of age, he still has a lot to offer.
"The one-year contract, which has the option to be extended beyond that, has been structured in a way which should ensure he focuses on his performances on the field."
Pennant has made more than 70 appearances for the club but fell out of favour last season, spending a three-month loan spell with Championship side Wolves.