Thao earned Vietnamese athletics' first ever Asiad gold medal, and the country's second gold this year, with a best jump of 6.55 meters.
The silver medal went to India's Neena Varakil, 6.51 meters, while China's Xu Xiaoling took the bronze with a leap of 6.50 meters.
Thao managed to achieve her medal-winning result in her first attempt. She was unsuccessful in improving her results with later attempts, but none of her opponents was able to beat her result. Silver medalist Varakil achieved her best jump in the fourth attempt.
"When Thu Thao jumped 6.55 meters, I was still worried because Thao's opponents had achieved far better results before. Both the Chinese and Indonesian athletes had jumped further than 6.70 meters," Thao's coach Nguyen Manh Hieu told VnExpress.
"However, in a high-pressure tournament like Asiad, it is not easy to achieve your best possible results."
At the 2017 Asian Athletics Championships, Thao had also won the long jump gold medal with a jump of 6.54 meters. Her best result however was 6.68 meters at last year's SEA Games in Malaysia.
Vietnam now has two gold, 11 silver and 13 bronze medals in various sports.
About 18,000 athletes and officials are in Jakarta and co-host city Palembang for the Asian Games, a regional contest featuring 40 sports.
The Vietnamese delegation has 532 members, including 352 athletes.