The former Germany international has spent the last 14 years at Signal Iduna Park, winning three German titles and one DFB-Pokal.
Kehl will hang up his boots at the end of the current campaign, with just a home game against Werder Bremen and the cup final versus Wolfsburg to come.
"I've always wanted to go out on a high level," he said at a press conference.
"It's great. You can't write a better script, with a final in Berlin and possibly a trophy in my hands.
"When I made the decision, it wasn't clear how the year would pan out and I was wondering whether it was the retirement I'd like.
"It's the right time to stop. There's only a few days until I enter the stadium for the last time. It will be emotional."
Dortmund are three points behind sixth-placed Augsburg going into the final weekend of the season as they look to sneak into a Europa League place.