Of course, the comment section was filled with positive remarks, with many of her reality TV co-stars obsessing over her new look.
"Name her GOALS," Dorit Kemsley said.
"OMG," Kylie Richards wrote.
Other celebrities like Emma Roberts and Cindy Crawford commented on the snap, along with Rinna's two daughter's Amelia Gray and Delilah Belle.
While we've never seen Rinna go blonde before, this isn't the first time she's experimented with her look. On this season of the RHOBH, the actress sported a brown lob, a slicked back long ponytail and a super short boy cut.
WATCH: Rinna shows off her wavy brown lob