The Jamaican, who clocked an Olympic record 9.63 to retain his 100m crown on Sunday, cruised to victory in 20.39.
Bolt has said he needs to win 200m gold again before he achieves his aim of becoming a 'legend'.
'It was an easy run, I'm enjoying it, it's my favourite event,' said Bolt. It's getting pretty chilly. They say the weather should be good on Thursday [for the final] so we'll see.'
Bolt's countryman and training partner Yohan Blake also breezed through, slowing down well before the line to clock 20.38.
France's Christophe Lemaitre went quicker than both Jamaicans in winning his heat in 20.34 and Bolt nodded in approval as he watched his rival's run on a TV screen.
The USA's Maurice Mitchell won the third heat in 20.54, while there were also wins for Jamaican Warren Wier, Alex Quinonez of Ecuador and Churandy Martina of the Netherlands.