A father was stabbed to death by his teenage son inside their Brooklyn home, cops said Sunday.

The 56-year-old father, Mohammad Razzaq, was discovered lying face up in the living room around 10 p.m. Saturday, after police responded to an assault at 644 East 3rd Street in Kensington, cops said.

His son, Hassan Razzaq, 19, was arrested for allegedly stabbing his father in the throat with a kitchen knife, sources said.

It is not immediately clear what the motive was, police said.

The teen was charged with murder and criminal possession of a weapon.