The “vulgar” stunt went viral on Weibo, China’s most widely used social media platform, and showed the pig being carried by two men up a metal staircase onto the platform.
The 75kg pig, which had its feet tied up so it could not escape, was then dressed in a cape and secured to bungee ropes before being pushed off.
Squeals can be heard from the pig as it plunged down, accompanied by laughter and cheering from a crowd that had gathered to watch.
The theme park, located in the south-western municipality of Chongqing, said the stunt was meant to promote the opening day of the park’s bungee attraction on 18 January.
It said in a statement: “We sincerely accept netizens’ criticism and advice and apologised to the public.
“We will improve [our] marketing of the tourist site, to provide tourists with better services.”
The Chinese public condemned the act, calling it animal cruelty and “torture”.
One commenter said: "You can't torture pigs just because the Year of the Pig has passed."
Another said: "This is animal cruelty, no doubt about it. I recommend we tie the organiser up to do the bungee jump instead."
According to local reports, the park’s owner said: “We let the pig make the first jump [on our opening day] because pork prices have been very high this year and recently they dropped a bit.”
A public relations officer reportedly added the pig was taken to a slaughterhouse after the incident and its trauma during the stunt was “just a bit of entertainment”.
Animal cruelty is not prohibited in China, but a growing awareness of animal welfare issues in recent years has seen petitions and calls for the government to implement policies.
Jason Baker, PETA Asia's Vice President of International Campaigns, told the Independent: "This is cruelty to animals at its worst. A bungee jump is a scary experience even for consenting humans – just imagine the outright terror of being forcibly strung up by your legs and thrown from a high platform. That's the treatment that this pig received, all for a cheap laugh.
"Pigs experience pain and fear, just as we do, and this kind of disgusting PR stunt should be illegal.
"The theme park deserves every shred of the backlash it's receiving online, and the Chinese public's angry response should be a wake-up call to China's policymakers that they must implement animal protection laws immediately," he added.