On a sweaty, sticky night in the Bird's Nest, Bolt was out of the blocks quicker and opened up an unassailable lead over the first 100m before coming away down the straight and jabbing his thumbs at his chest as he crossed the line.
His 19.55 seconds was the fastest in the world this year, his speed and peerless championship class too good for American Gatlin, whose 19.74 was well outside his season's best.
Jamaican Bolt, who will also compete in the 4x100m relay, said: "It means a lot to me.
"I'm happy to be a 10-time World Championships gold medallist, especially when people have been saying I would lose.
"I had the utmost confidence. As long as my coach is confident, I'm super confident.
"The British people give me a lot of love
His 19.55 seconds was the fastest in the world this year, his speed and peerless championship class too good for American Gatlin, whose 19.74 was well outside his season's best.
Jamaican Bolt, who will also compete in the 4x100m relay, said: "It means a lot to me.
"I'm happy to be a 10-time World Championships gold medallist, especially when people have been saying I would lose.
"I had the utmost confidence. As long as my coach is confident, I'm super confident.
"The British people give me a lot of love