Dennis Rodman just added more ink to his body to honor his girlfriend ... this time, he got a huge photo of her face tattooed right on his butt cheek.
The NBA legend hit up an artist in Florida this week to get the piece done -- the second time this summer he's gotten a tribute tat for Yella Yella placed on his body.
You'll recall, the first time was back in July -- when he got her portrait put on his face. This time around, he opted for his backside ... while adding a photo of his face to the imagery as well.
Rodman shared a video of the whole process on his social media pages on Thursday ... revealing Yella Yella had no idea of his plans when the two went on a late-night venture to the tattoo parlor.
In the footage, you can see the tats came out great ... taking up one-half of the 6-foot-7, former basketball player's butt.
We've yet to hear Yella Yella's reaction to it all -- but the last time around, she told TMZ Sports that while she thought he was wild for getting the work done, she was appreciative of the gesture.