Sting says he was driven to music as a boy after he walked in on his mother making love to the milkman.
In his new autobiography, the star claims the pivotal moment turned him to music as a way of coping with his emotions.
Sting said playing the piano provided comfort from his parents' unhappy marriage.
In an extract from his memoirs Broken Music, Sting said he found out about the affair with one of his milkman father's employees when he awoke early for school.
"As I turn the handle on the door there is a sudden panic on the other side of the glass. I manage to open the door only a crack before it is violently shut again," he said.
"I have seen nothing but I run and behind me I hear the front door slam. My mother doesn't find me when she comes up to my room."
He had no idea if his father knew of the affair but the milkman, Alan, disappeared from his job shortly afterwards.
Sting added: "Without the piano an outlet, I might well have become delinquent. God knows I had the contacts."
