The victim was five-year-old Casa Boy, who fell heavily in the Ace Radio Maiden Hurdle at Warrnambool yesterday. It was only his second jumps start.
Casa Boy fell around the 1000-metre mark, about a third of the way into the race, and broke his shoulder.
Screens were placed around the horse before he was euthanised.
However, the sport's backers, while acknowledging it was not a good start to the season, have said the fatality rate is at its lowest in 25-30 years.
Two other horses also fell during the Warrnambool meeting - Olympic Light and Chatillion - but neither was seriously injured.
Jumps racing has had a controversial run in recent years, with Racing Victoria ultimately pressing ahead provided there is no more than 0.65 per cent of fatalities per starters in hurdle and steeplechase races.
The fatality rate in 2010 was 0.41 per cent and in steeplechases it was 0.57 per cent.
It invested heavily in new jumps last season in a bid to keep the toll within limits.
The Victoria RSPCA, which opposes jumps racing, said in a comment before the start of the season that the state's new Minister for Racing, Denis Napthine, was clearly a supporter of jumps racing.
"We need to illustrate to him, a key decision-maker, that this cruel sport is not accepted by the community.
"Racing Victoria is receiving pressure from pro-jumps racing groups and it is important we show that we will not be letting them of the hook either.
"Racing Victoria must take further action to ensure horses no longer suffer for a sport that is not favoured by the community.
"Jumps racing loses money and is ruining the reputation of the entire racing industry."