Scores of competitors from the 370-member Australian team were standing on a temporary bridge over the Yarkon River ready to lead a march into the Ramat Gan Stadium near Tel Aviv for the 27-nation Maccabiah Games, nicknamed the "Jewish Olympics".
Police said one person was killed and 45 were injured, at least three seriously, when the wooden bridge supported by metal bars collapsed in the middle.
Israel's Itim news agency said the dead person was an Australian woman about 50 years old but this could not be confirmed. Two rescue workers were also injured. The bridge was specially built for the games.
"It didn't stand up to the weight," said Public Security Minister, Avigdor Kahalani. He said there was no suspicion of foul play and an engineer had previously declared the bridge fit for use.
Louis Platus, head of the Australian delegation, said: "About 100 of us were on the bridge when it collapsed at our feet."
Harry Purcell, the Australian team manager, said: "We were walking across. All of a sudden we heard a bang. And then it just collapsed in the middle and we started to slide."