Rough Night's death from a broken leg is the 10th in the state this year, and the fifth since Racing Victoria resumed the sport in May under revised rules intended to make jumping safer.
The horse was brought down by another falling horse, Royal Laddie, in the second race at Warrnambool, and was put down on the track.
Animals Australia executive director Glenys Oogjes called on Victoria's racing minister Rob Hulls to intervene to "prevent further deaths".
"I call on the Racing Minister to intervene immediately to stop this cruel and deadly 'blood' sport.
"The death of Rough Night at Warrnambool is surely enough for Minister Hulls to see that Racing Victoria cannot stop this ridiculous and tragic toll from rising."
Oogjes said the minister "has effectively assigned the fox to look after the chickens" in leaving Racing Victoria in charge of jumps racing.
"The rate of falls and deaths so far this season exceeds what the minister has described as 'unsustainable' last year, and is the highest death rate for the past 35 years," she said.
"So Minister, how much suffering and how many horse deaths will it take before this cruel sport is ended in Victoria?" she said.
Racing Victoria suspended jumps racing on May 7 following three deaths at the Warrnambool racing carnival, including two in one day.
An urgent review was conducted and 11 days later Racing Victoria announced a resumption with new conditions aimed at making the sport safer, including removal of the last hurdle and further jockey education.
It promised a further review of jumps racing at the end of the season.
However, welfare groups have been vocal in their criticism of the sport, saying previous safety reviews have done nothing to reduce the toll.
They point out that horses die in jumps racing at a rate 10 to 20 times that of starters in flat racing.
Twelves horses died at official jumps races in Victoria during the 2008 season, and another died at a trial.
Jumps racing now takes place only in Victoria and South Australia.
Rough Night's death will go before Racing Victoria's jumps review panel, which has yet to report back on the death of top jumper Geeorb little more than a week ago.