The most recent accident saw Hanging Rock destroyed on Sunday at Yarra Valley after breaking his leg while leading a race.
His demise follows the deaths of two Victorian jumps horses, Taken at the Flood and Wool Zone, in South Australia on Saturday, and the death of Shrogginet in a trial at the Cranbourne Training Centre last Thursday.
"The Brumby government can no longer ignore the carnage," said Glenys Oogjes, executive director of welfare group Animals Australia.
"Racing Victoria might be willing to turn a blind eye as the horses topple over jumps and are destroyed but the community is appalled.
"Nothing short of a ban is now acceptable," she said.
The group called on Victoria Racing Minister Rob Hulls to intervene and call a halt to the jumps races scheduled for the Warrnambool May Racing Carnival, beginning on May 5.
Oogjes says six horses have died in the last three seasons on the Warrnambool jumps track.
This year's carnival includes five jumps races over three days, culminating with the Grand Annual Steeple over 5.5km and 33 jumps - the longest race in Australia, and most jumps of any jumps race in the world.
Victorian Advocates for Animals also called on the minister to stop the races.
President Lawrence Pope told Melbourne's Herald-Sun newspaper that 60 jumps races were left in a long season and it was looking to be just as bad as last year.
During the 2008 season, 12 horses died at official jumps races in Victoria and another died in a trial.
Statistics show that the death rate among horses in jumps racing is 10 to 20 times that of flat racing.
An inquiry was launched at the request of Victoria's racing minister last June.
The resulting report by former Country Court Judge David Jones was released last December and recommended significant changes to jumps racing tracks, jumps and training of horses and jockeys to reduce the death rate.
Jumps racing in Australia now only occurs in Victoria and South Australia.
Last December, Animals Australia slammed Racing Victoria's decision to allow jumps racing to continue, subject to reforms in the Jones report.
Oogjes said Animals Australia had provided evidence to Judge Jones that previous jumps racing reviews, in the 1990s and in 2002 and 2005, had made no difference to the injury and fatality rates.
"It is deeply distressing that yet more so-called 'reforms' have been recommended," Oogjes said at the time. "They will fail, as have all previous 'reforms' ... it is the jumps horses that will be forced to test the changes.
"It is inevitable that some otherwise healthy horses will pay with their lives."