After crossing this bar on the third try, the world record holder (6.21 m) decided to stop his competition.
He beat Norwegian Sondre Guttormsen (5.73m) and Filipino Ernest John Obiena (5.73m).
"Mondo", 22, broke the meeting record (5.91 m) held by French Olympic champion Renaud Lavillenie since 2017, present at the meeting but who could not cross any bar.
Lavillenie, 35, missed his three attempts at 5.63m, while French champion Thibaut Collet failed to pass 5.53m.
Duplantis is already guaranteed to win its second Diamond League after skipping meetings in Doha, Eugene, Oslo and Rome.
The Chorzow stage did not count for the final classification.
Duplantis gleaned his first outdoor world title in Eugene (United States) at the end of July, his fifth international senior title since 2018.
© 2022 AFP