The 43-year-old actress is departing her recurring role as a political reporter on the CBS drama to recover from the injuries she sustained when hit by a piece of lighting equipment on the set of the show last month.
She said in a statement: "It is with deep regret to inform everyone that due to my injuries, I am unable to return to The Good Wife at this time. I'm getting better slowly, and thank you everyone for your concern."
Kristin's final appearance on the show will be the season four premiere, which airs next month, but show bosses haven't ruled out a return in future.
A source told Us magazine.com: "She may return in the future, but right now she needs more time to heal. The producers said she is welcome back any time."
It is unclear what is exactly wrong with Kristin, who was hospitalised after she was struck by the lighting silk on Kent Avenue in the Williamsburg area of Brooklyn, but released a day later.
Her representative said in a statement at the time: "Kristin has been released from the hospital and is home recovering. She thanks everyone for their prayers and well wishes."
Following the incident, Will and Grace actor Sean Hayes - who starred opposite the blonde in Broadway production Promises, Promises in 2010 - took to his twitter account to wish the actress a "speedy recovery".
He tweeted: "Sending out my love and wishes for a speedy recovery to my former leading lady, @KChenoweth."
Kristin has previously starred in The West Wing, Glee, Four Christmases, The Pink Panther and Pushing Daisies.