The 27-year-old has joined Stoke on a two-and-a-half-year contract after impressing during a four-month loan spell with the Potters.
“We have been working very hard over the past couple of weeks to do the right deal for this club,” Stoke boss Tony Scholes told the club’s official website.
“We are delighted to secure Jermaine’s long-term future at the Britannia Stadium because over the past few months he has emerged as a key figure in the manager’s plans.”
Stoke manager Tony Pulis said: “This is fantastic news, just what we all wanted.
“Jermaine has made such a big impact since he has been with us and he has become a big favourite with the supporters, so I know that everyone will be delighted that we have completed this signing.
“The important thing has been getting him comfortable and settled, and now that we have done that I am sure he can go on to play an even bigger part in our plans.
“Natural wingers are hard to come by, but we have two of them with Jermaine on the right and Matty Etherington on the left, so that gives us a real threat down both flanks.”
“I think everyone knows how I feel about being at this football club,” Pennant said.
“The supporters, players and management have been absolutely fantastic to me over these past four months and I desperately wanted to stay here because I love it so much.”
He added: “I know I have only been here a few months, but it really does feel like I have been here for years.
“The atmosphere around the place is brilliant, so I am looking forward to the fact that I am here at Stoke now for the long term and back in the best league in the world.”