The network announced that the show's seventh season in 2011 is to be its last.
Turner Entertainment Networks president Steve Koonin said: "The Closer was a pivotal series in setting a new course for TNT's original programming, while also serving as a prime example of the storytelling strength possible on cable television."
The show's Emmy-winning lead actress Kyra Sedgwick added: "I cannot fathom how difficult it will be to say goodbye to the incredible family we've created on The Closer. I will always be grateful to [series creator] James Duff for his love and friendship, as well as for creating such a rich and complex character who I have loved living with year after year."
The series, which began in 2005, will air its 100th episode during its final season next year.