Li broke an eight-year-old world record in the snatch when she lifted 103 kilograms, beating the mark set by North Korea's Ri Song Hui at the 2002 Asian Games. She then lifted 127 in the clean and jerk for a total of 230 kilograms, improving the world record for the combined mark.
Qiu Hongxia, also from China, set the previous combined world record of 226 kilograms in 2006.
Zulfiya Chinshanlo from Kazakhstan won silver with a combined total of 219, while Prapawadee Jaroengrattanatarakoon (215) clinched bronze.
Li's world record effort helped China to its fourth gold from four finals so far at Guangzhou.
“It's a very happy moment for me,” said Li, who bowed quickly to acknowledge the record lift.
The Chinese government has promised $10,000 to every athlete who breaks a world record in the Asian Games, but Li said: “I haven't thought about how I would be spending it.” Li was not totally satisfied with her clean and jerk performance, which was two kilogram less than the world record of 129 kilogram she set three years ago.
Like Li, the 23-year-old Zhang was also not entirely happy with his gold medal effort, as he failed in his first attempt at a world record of 182 kilograms in clean and jerk.
“It was not good enough and hopefully I will improve in future,” he said.
Zhang said the world record was on his radar and he might make an attempt in the first half of 2011 before tuning up for Olympics in 2012.
“I might attempt 327 or 328 maybe next year if I stay fit,” he said.
Meanwhile an established Olympic swimming superstar and a seven-month pregnant shooter helped South Korea to one of its best days at the Games.
Park Tae-hwan, the 400-meter freestyle gold medalist at the 2008 Beijing Olympics, won the 200 freestyle in the Asian Games pool, leading throughout to break his own Asian record.
Hours earlier, Gim Yun-mi, who is expecting a child in two months, helped out as South Korea swept all four shooting gold medals to give it nine on the day overall.
China collected 18 golds Sunday and moved to a leading 37 on the second day of competition at the Games, which end Nov. 27. China topped the medal count at the last Asian Games in Doha with 166 gold medals and is on its way to repeating that. There are 476 gold medals to be awarded in Guangzhou.
South Korean shooter Lee Dae-myung won the men's 10-meter air pistol and helped secure a victory in the team competition on the second morning. Later, Gim won the women's 10-meter air pistol and helped South Korea win the women's team gold.
“I got the gold medal with my baby, I feel so happy,” Gim said through an interpreter.
Jia Rui helped deliver Macau's first-ever gold medal at the Asian Games by winning the Daoshu/Gunshu all-round title in the Chinese martial arts of Wushu.
Macau had won five silver and 10 bronze medals in previous Asian Games, but the 23-year-old individual world champion clinched Sunday's gold with an acrobatic routine involving flips and fast sword movement.
India, meanwhile, won its first gold of the games when Pankaj Advani beat Nay Thway Oo of Malaysia 3-2 in men's English billiards.
Japanese triathletes finished first and second in the men's race just 24 hours after two of their female compatriots took the major medals in the women's event.
On Sunday, Yuichi Hosoda and Ryosuke Yamamoto finished one-two to make Japan the undisputed triathlon champions of the Asian Games.
At the Asian Games pool, Park broke the Chinese domination that has seen the host country win nine golds in 12 finals over two nights.
Japanese star Kosuke Kitajima failed to win his 50-meter breaststroke heat in the morning and struggled again in the final, finishing 0.35 seconds behind winner, China's Xie Zhi, to end up in a dead heat for fourth with Iran's Mohammad Alirezaei Dizicheh. Kitajima's teammate Ryo Tateishi was second.
The 50 distance is not the 28-year-old Japanese star swimmer's best event - he swept the 100 and 200 Olympic titles in Athens and Beijing. Still, failing to land a medal at all is a worrying sign heading into his signature events in Guangzhou.
Kitajima said the competition was simply too strong.
“Even though it's my best result of this year, I did not get a medal,” he said. “I'll try my best in the 100-meter breaststroke later.”