The second gold for Team China came from Chen Yiwen in the women's 1m springboard, proving her home country is a diving powerhouse.
The Chinese tandem scored a total of 439.74 points after six attempts, followed by Jack Laugher/Daniel Goodfellow of Britain with 415.02 and Juan Manuel Celaya Hernandez/Yahel Castillo Huerta of Mexico with 413.94 respectively.
"It was our second time as mixed platform partners, and also my second World Championships. I was happy that we won the first gold medal in diving for Team China in Gwangju," 19-year-old Lian said.
Kristof Rasovszky of Hungary won the men's 5km open water race on Saturday, taking his first career world title. He finished in 53 minutes and 22.10 seconds, becoming the first gold medalist in Gwangju.
Sarah Bacon of the United States took the silver with 262.00, and Kim Su-ji of South Korea placed third with 257.20, becoming the host nation's first diver to reach the podium in the biennial event.
"I did not perform my best today, but fortunately we were the champions. Since mixed synchro is not an Olympic event, I need to fight for the Olympic tickets in the single and synchro," said the 10m synchro champion in Budapest World Championships two years ago.
The Russian swimming star teamed up with Svetlana Romashina, sealing first in the duet technical trials with 95.95001. The duet technical finals are scheduled for Sunday.
Chen, fourth place finisher two years ago in Budapest, led the field from the first dive, earning a combined 285.45 points.
Logan Fontaine of France was the silver medalist in 53:32.20, and Eric Hedlin of Canada got the bronze in 53:32.40, just 0.2 seconds behind the runner-up.
GWANGJU, South Korea, July 13 (Xinhua) -- Team China dominated the second day of the 18th FINA World Championships, snapping up three out of the five gold medals up for grabs in the swimming competitions here on Saturday.
With the three golds, China was atop the medal table, followed by Russia with one gold and one silver and Hungary with one gold.
Si, winner of women's 10m platform in 2013 Barcelona worlds and mixed platform synchro champion in 2015 Kazan worlds, was disappointed at her performance.
"I did not win a medal in Budapest, and now I lived up to my dream with the gold. I was very happy that all the efforts were paid off because we had a six-week training camp for the World Championships in Jinan, China. It helped me a lot," said the 20-year-old Chen.
They were trailed by Ekaterina Beliaeva/Viktor Minibaev of Russia with 311.28 and Maria Jose Sanchez Moreno/Jose Balleza Isaias of Mexico with 287.64. British pair Noah Williams/Olivia Rosendahl finished fourth with 285.18.
Chinese swimmer Qiao Zhonyi finished 13th among 61 contestants at 53:37.500, just 5.40 seconds behind the runner-up. His teammate Cheng Long came in 45th at 54:18.70.
Lian Junjie/Si Yajie, the World Cup winners last year, awarded China the first gold in the mixed 10m platform synchronized. The Chinese divers built up the lead from the beginning to the end, collecting a total of 346.14 points.
China won its third title in the diving competitions as Xie Siyi and Cao Yuan settled for gold in the men's synchronized 3m springboard. The duo won the silver in the event in Budapest two years ago.
Defending champion Svetlana Kolesnichenko of Russia took gold in the solo technical artistic swimming with 95.0023 points, followed by Ona Carbonell of Spain with 92.50002 and Yukiko Inui of Japan with 92.50084.杭州桐乡银钻