Originally 20 swimmers were due to contest the championship, but event organisers were told only five will attend.
The Chinese Swimming Federation said it was because of a national competition starting in September. However, the move comes after two leading Chinese swimmers failed drug tests.
Terry Gathercole, the Australian Swimming president, said: "It's difficult for us to understand their philosophy. They could be embarrassed but then again they might just say they can't afford it.
"Those of us who have been in the sport for some time and remember the East Germans, well, it leaves you wondering. You have to speculate why the other swimmers aren't coming.
"I'm sure if you ask them they'll probably say that they weren't swimming well enough or they weren't able to finance such a large team. But I think people will be able to judge for themselves."
Gathercole said comprehensive drug testing would be carried out at meeting.
Susan O'Neill, the Olympic 200 metres butterfly champion in 1996, was disturbed by the news. "It's just really suss [suspect], I haven't got any respect for Chinese swimmers to be perfectly honest," she said. "They've cheated over the years and there's been evidence to prove it so... hopefully they won't turn up at the Olympics either."
Chinese swimmers have been attracted doping allegations since the 1994 World Championships. Criticism came to a head in 1998 at Perth when 13 vials of growth hormone were seized from a swimmer arriving in Australia. Another four swimmers tested positive at the meeting.
Last month, two Chinese swimmers returned positive drug tests. One of them, Xiong Guoming, had previously served a two-year ban for steroid use.Reuse content