A naked sunbather unashamedly gave chase in his birthday suit after a wild boar stole his laptop while he was relaxing by a Berlin lake in an escapade that has gone viral.

The man was pictured running after the cheeky swine at the Teufelssee lake, a popular spot for nude sunbathing.

Adele Landauer, the Berlin-based life coach who took the pictures, shared them on her Instagram account, describing the man as a "real hero".

"A female wild boar with two babies came out of the forest in order to search for food," she wrote.

"Many of us were scared but the wild boars seemed to be peaceful.

"After they ate a pizza from a backpack of a man who was taking a swim in the lake they were looking for a dessert. They found this yellow bag and decided to take it away."

The owner of the bag immediately leapt up in pursuit, since the bag had his laptop inside.

"Every one of us adored him, how focused he stayed, and when he came back with his yellow bag in hand we all clapped and congratulated him for his success," Ms Landauer wrote.

"This happens when you're focused on your goals," she added.

Ms Landauer had originally published the photos on a personal social media account yesterday, with her post being shared thousands of times.

The man laughed when she showed him the photos and asked permission to share them, she said.

"I believe life has its funny sides and we should share them," she added.

Ms Landauer was shocked by the attention her photos have received.

"Of course I was totally surprised -- nobody can expect such a strong interest," she said.