A video showing a koala doggy paddle across Kangaroo Island's Harriet River is thrilling thousands of social media users across Australia.

The video was posted on Facebook by Mandurah couple, Joe and Jas, who are travelling around Australia and blogging their adventures online.

On the March 11 post, Joe and Jas asked "have you ever seen a koala swim?".

"We hadn't until we bumped into this little cutie having a cool off. Check out that doggy paddle."

The video has been viewed almost 8,000 times and had 189 shares on Facebook.

While the tree-dwelling mammals have been known to drown in backyard swimming pools when searching for water, they can actually swim provided they have a way of getting out of the water.

This particular koala made it safely across the river, and, according to the Facebook post, was later spotted having a snooze up a tree.