The 26-year-old Jamaican, who won the 200m titles in Berlin in 2009 and Daegu in 2011, and is also double Olympic champion and world record holder in the event, timed a comfortable 20.13sec to win his heat and advance to Saturday’s final.
After a good start, Bolt was up on compatriot Jason Livermore in the lane outside him within a matter of metres.
He held his form and came through the line just one-hundredth of a second ahead of South African Anaso Jobodwana, who finished eighth in the final at the London Olympics and looks in impressive form in Moscow.
Bolt, who admitted earlier Friday that he had been nursing a sore foot after regaining his 100m title on Sunday, will be joined in the final by teammates Warren Weir, the Olympic bronze medallist, and Nickel Ashmeade.
“I tried to take it easy, I was watching the American guy (Isiah Young, who finished third) and tried to pace myself,” Bolt said.
“Then I heard footsteps and heard the South African guy coming so I had to change gears a little bit.”
Bolt added: “I will have a good day’s rest and go into the final and get it done.”
American Curtis Mitchell blasted to a personal best of 19.97sec to win his heat ahead of Weir.
“The PB was down to execution. I stayed relaxed and focused,” said the unheralded Mitchell, who is in the same training group as doping-tainted American sprinter Tyson Gay.
“I’m not really surprised because my coach told me that this will happen if I execute well.
“My coach also told me that a semi-final is like a final so I gave everything and did not slow down on the last 10 metres.”
But Mitchell will be the sole American in the eight-man final.
His teammate, four-time world medallist Wallace Spearmon, could only finish sixth in his heat in 20.66sec, while Young failed to grab one of the two fastest loser spots.
Other sprinters going through include Britain’s Adam Gemili, who ran a personal best of 19.98sec to win the third and final heat.
“It’s the best feeling in the world. I am over the moon,” said the Briton who was overlooked for the 100m, previously regarded as his speciality.
“I made the final with the best 200m guys in the world. It’s crazy, crazy.”
Completing the line-up will be Churandy Martina of the Netherlands and Norway’s Ghana-born Jaysuma Saidy Ndure.
Bolt has kept a low profile since he powered to victory in Sunday’s 100m final, regaining the title he lost when he was disqualified for a false start in Daegu two years ago.
A gold on Saturday would push him one step further to equalling the present mark of eight world gold medals won by retired American duo Carl Lewis and Michael Johnson.