The caretakers at Senkwekwe take great care to not put the health of the gorillas in danger.
He works for the park's anti-poaching unit, and the gorillas in the photo, Ndakazi and Ndeze, are both orphans who have been raised in the park.
Another said it was the "Best picture ever", and another user added: "A special thank you to you and your colleagues for helping to protect these beautifull gorillas, stay safe".
"You might have recently seen caretakers Mathieu and Patrick's unbelievable selfie with female orphaned gorillas Ndakazi and Ndeze inside the Senkwekwe center at Virunga National Park", they wrote.
Two orphaned mountain gorillas struck a pose recently that looks like it could have been a scene from any backyard barbecue or house party.
The picture was taken at Virunga National Park - a UNESCO World Heritage Site.
The gorillas have lived in the sanctuary since infancy. A set of photos taken by their friendly protector shows one gorilla placing its hands on its hips and tossing its head back, and another coolly draped over its human friend's shoulders.
The selfie taken by Ranger Mathieu Shamavu quickly went viral during the past week for obvious reasons.
"Five rangers were killed in Virunga National Park past year in an ambush by suspected rebels, and more than 130 park rangers have been killed in Virunga since 1996", it added.
Mountain gorillas are some of the most endangered creatures on Earth.