The 26-year-old was spotted wearing the sparkler as she accompanied her man to the Ignite Angels and Devils Pre-Valentine's Day Party in Bel Air, California.
It's the first time the ring has been on her finger since she revealed that she and Offset had split late last year (2018), following rumours suggesting her had cheated on her.
Migos star Offset handed Cardi the 8-carat, pear-shaped halo diamond ring when he proposed during Power 99's Powerhouse concert in Philadelphia, Pennsylvania in October, 2017. The following June - a month before she welcomed their baby daughter Kulture, the "Bodak Yellow" star revealed the couple had married in secret.
The pair's winter split didn't last long and Cardi and Offset were spotted hanging out in Puerto Rico together before her performance at San Juan's Electric Holiday Concert.
"(We are) just taking things slow," she told People at the time. "I hang out with him, I talk to him every day and we do our thing."
But asked if she and her estranged husband would be getting back together permanently during a recent Harper's Bazaar interview, she said, "I don't think so. Who knows? You never know, you can never tell."
The couple seemed loved up when Offset joined his wife onstage at the Grammy Awards on Sunday, February 10, when she made history as the first female artist to pick up the Best Rap Album honour.