The actress was a part of on the NBC show during its 13th season.
She will be leaving at the beginning of the 24th season that is scheduled to air in the near future.
The speculation has been widespread lately about whether Giddish could be planning to surrender her license.
"I wanted to address the chatter I've seen online and let everyone know that
This will, indeed, be my last season on Law & Order: SVU," Giddish said in an announcement.
"Playing Rollins has been one of the greatest pleasures my life.
I've been blessed to be member of this Law & Order family for the past 12 years.
There's simply no TV character like Rollins. She's matured and changed and I've done too.
I began watching this program when I reached my mid-late 20s, and I'm glad