The Olympic champion had broken his own world record with a stellar effort of 6.24 metres at the Xiamen season opener last week and wrapped up another victory in China with his best of 6.00m too good for the rest of the pack.
With the bar raised to 6.25m, Duplantis was primed to break the mark for a ninth time but he was unable to clear the height in his three attempts, coming agonisingly close in his final chance to leave fans disappointed.
"I felt great today, really good. To jump 6.00m today and complete a successful tour, I have a lot of good takeaways," Duplantis said.
"I felt a little bit flat today, but still really good. I just feel conditions have to be perfect for me to jump a world record and I wasn't quite feeling it off the runway tonight.
"Now I go back home and train for a few weeks until my next competition in Ostrava."
Ben Broeders of Belgium and Sam Kendricks of the United States managed vaults of 5.82m behind the winner.
Akani Simbine powered to victory in the men's 100m race in the Shanghai leg of the premier track and field series which is being held in the neighbouring city of Suzhou this year due to stadium renovation.
The South African made a good start and crossed the finish line in 10.01 seconds to deny reigning Diamond League champion Christian Coleman of the United States back-to-back victories this season.
Coleman's pace dropped towards the end and he settled for silver with a time of 10.04 seconds, ahead of compatriot Fred Kerley who clocked in at 10.11 seconds for bronze.
Briton Daryll Neita stunned pre-race favourite Sha'Carri Richardson in the women's 200m with a time of 22.62 seconds.
"I feel amazing. It was such a strong field and to run that time at this stage of the season is amazing," Neita said.
"My main focus for the rest of the season is to stay healthy and in one piece. I hope to win a medal at the Olympics."
Richardson, the winner of the 200m bronze at last year's world championships, was third behind fellow American Anavia Battle who came in at 22.99 seconds.
World champion Marileidy Paulino of the Dominican Republic backed up her gold from Xiamen by cruising to the women's 400m gold in 50.89 seconds.
She was comfortably ahead of American Talitha Diggs and Barbadian Sada Williams to put down a marker for the Olympics which will be held in Paris.
In the dramatic women's 100m hurdles, world-record holder Tobi Amusan was disqualified following a false start before the Nigerian ran under protest and finished first ahead of Jasmine Camacho-Quinn.
Barring a successful appeal from Amusan, Olympic champion Camacho-Quinn will earn a second victory of the season with her effort of 12.63 seconds.
"I was ready to throw it. It took such a long time to get going," said Camacho-Quinn.
"I'll take the points and take a break. I can't believe the time, but it is what it is. There were three of us in a line, so I didn't know who had won.
"These meets are just preparation (for the Olympics) and I know what I need to work on."
Ethiopia's Olympic 10,000m champion Selemon Barega won the men's 5000m in 12:55.68 while Kenya's Beatrice Chepkoech took gold in the women's 3,000m steeplechase.
The Diamond League season continues in Doha on May 10th.
A bumper 15 meetings have been scheduled this year, with the season finale scheduled for Brussels in mid-September following the July 26th to August 11th Olympics.
