Thompson's dominant victory emulated American Florence Griffith Joyner, the last woman to win both 100 and 200 gold medals at the same Games.
Racing with a sparkly headband, Thomson made a brilliant start that helped her surge ahead of the field and after the bend she never looked like relinquishing her lead to win in 21.78 seconds.
Thompson's victory over pre-race favourite Dafne Schippers of the Netherlands ensured Jamaica maintained its grip on the Games' most prestigious sprinting titles.
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"My school motto was 'let the light shine' and I let my light shine tonight," Thompson told reporters.
"It's a big surprise to me because I have had a hamstring injury. You must overcome these things and tonight I am standing here with a gold. To beat Dafne is a hard run."
After the race Thompson said she was shocked by her Rio success and revealed she had watched on the internet Joyner's races from 1988. The Jamaican was born in 1992.
Thompson, who won a 200m silver in the 2015 world championship, also credited her stunning performance to being able to overcome the hamstring injury sustained during the Jamaican Olympic trials.
"I had rough days training but I did not let that overcome me. I'm a warrior," she said.
Schippers, the world champion in the event, ran her fastest time of the season in the final, clocking 21.88 seconds but she was still disappointed by the result.
"I haven't made my mind up about what happened. I'm not happy with the silver," Schippers said.
"I came for gold. I was in good form. My times were okay but they were not strong enough. It's heavy to run six races."
Schippers sustained a leg muscle injury ahead of the 100m final and said she had almost pulled out of the Games.
American Tori Bowie, who won a silver medal in the 100m final, grabbed bronze, capping a meteoric rise for the former long jumper who only switched to sprinting in 2014.
"My goal today was to finish as best I could and I'm leaving with another medal," she said.
"Who couldn't be thankful for that?"
(Editing by Ed Osmond/Greg Stutchbury)
