An amazing video has emerged of a dog protecting a boy while his father pretends to hit him.

The footage, shot earlier this year in Calcutta, India, shows the dog barking at the man when he pretends to raise his hand on his son.

As soon as the man steps back, the dog stops barking.

"When incessant barking didn't do any favour, the pup held the hand of its owner to save his little friend from his father's beating or shouting" the filmer wrote online.