The 33-year-old originally planned to hang up his boots last summer but was convinced to play on for another season.
"Martin has been in our starting XI for 20 out of 21 competitive matches for us this season," said the club's director of sport Max Eberl. "He's an important lead figure in our team and we're delighted that we will have him with us next year too."
The Austrian said he decided to carry on playing since he still feels fit enough to do so.
"I feel very happy with Borussia and have always said that I would like to continue playing for as long as my body plays ball, for as long as the club would like me to play and while my family are happy here," said Stranzl.
"That is the case and therefore I'm delighted to be able to play another year with Borussia."
Stranzl joined the Foals from Spartak Moscow in January 2011 and made his 100th appearance for the club in last weekend's 1-0 loss to Bayer Leverkusen.