The 34-year-old Jane the Virgin star flashed her engagement ring in a birthday shoutout to her fiancé.
"Happy Birthday to my King," Rodriguez captioned the photo, which shows LoCiero wearing an adorable smile.
At the bottom of the shot, Rodriguez, whose face isn't in the photo, can be seen sweetly holding LoCiero's hand with her sparkler sitting front and center.
Rodriguez confirmed her engagement to PEOPLE on Tuesday, saying "I am [engaged]! He's the best. We've been engaged for like a month—I've kept it a secret for a while."
"'They thought I was a Surrealist, but I wasn't. I never painted dreams. I painted my own reality.'– Frida," Rodriguez captioned the photo quoting Mexican artist Frida Kahlo.
Rodriguez and LoCiero first met in 2016 after LoCiero made an appearance on Jane the Virgin.
The lovebirds have managed to keep their relationship pretty low-key, and Rodriguez plans on keeping it that way.
"I don't even really want to say it's happening," Rodriguez said.
"I just want to live! I think there's a huge blessing in the fact that people care. That's a beautiful thing, so that feels really good."
"But another part of me wants to keep a little something that's just mine, 'cause there's not too many things I have like that anymore," Rodriguez added.