The 20-year-old, China's most promising tennis prospect, persevered in the sweltering Hangzhou heat to defeat colleague Zhu Lin and win the match 6-2, 6-4 in 1 hour and 44 minutes.
Zheng Qinwen, who advanced to the quarterfinals of the US Open, defeated two top seeds to win the Asian Games women's tennis gold on Friday and enhance her rapidly improving reputation.
The 20-year-old, China's most promising tennis prospect, persevered in the sweltering Hangzhou heat to defeat colleague Zhu Lin and win the match 6-2, 6-4 in 1 hour and 44 minutes.
Zheng, who defeated world number seven Ons Jabeur to advance to the last eight at Flushing Meadows this month before losing to top-ranked Aryna Sabalenka, has had a breakout year.
She rose to a career-high ranking of 19 in May, and two months later she won her first WTA title.
Zheng's power and accuracy combined to win the match against Zhu in the final under the guidance of Wim Fissette, a mentor who previously coached Naomi Osaka and has also worked with Victoria Azarenka and Simona Halep.
In the first set, the world number 23 broke twice and dominated with her serve.
Zhu, who is 10 spots lower in the rankings, battled valiantly to stay in the game, recovering from a break down in the second set to tie the score at 3-3.
But Zheng persevered to break once again for 5-4 with a devastating cross-court forehand, and she kept her composure to serve out the victory.
Men's doubles gold was won by Taiwan's Hsu Yu-hsiou and Jason Jung, who defeated India's Saketh Myneni and Ramkumar Ramanathan 6-4, 6-4.
The top seed from China, Zhang Zhizhen, who advanced to the third round at both the US Open and the French Open this year, will compete against the second seed from Japan, Yosuke Watanuki, in the men's singles final on Saturday.
