Hollywood powerhouse Endeavor public has got a serious case of backstage jitters over its planned initial public stock offering, The Post has learned.

The firm headed by super-agent Ari Emanuel — which in addition to Hollywood’s biggest talent agency owns the Ultimate Fighting Championship and the Miss Universe pageant — is having trouble ginning up investor interest in the IPO — slated to price Thursday, sources told The Post.

The IPO, led by Goldman Sachs, has been targeted to raise more than $600 million by selling 19.3 million shares in a price range of $30 to $32. That implies a total value of $8 billion for Endeavor.

But the Los Angeles-based company, which in addition to Emanuel is headed by agent Patrick Whitesell, failed to wow investors at a recent road show presentation in New York, insiders said.

“It was not received well,” one source said of the road show. Another confirmed that “It’s fair to say there’s more work to do” when it comes to generating excitement on Wall Street.

One source said the price range could fall as low as $25 to $26 a share. Another source close the process said Endeavor hasn’t ruled out pulling the IPO, though others viewed that as less likely.

”It would surprise me if they pull [the IPO],” another source said, citing the fact that Endeavor already delayed the IPO over the summer.

Endeavor is pitching itself as a growth company that can seize on the volatility of the media industry, but there are some concerns about the company’s portfolio. The UFC, Endeavor’s biggest earnings driver, is facing an influx of competition, and WME is embroiled in a fight with the Writers Guild of America that threatens a key source of income: TV series packaging fees.

Sources said board members at the firm, which reps some of Hollywood’s biggest stars through WME, including Oprah, Adele, Dwayne Johnson, Rihanna, Drake, Matt Damon, Ben Affleck and Christian Bale, were slated to meet late Wednesday to discuss options.

An Endeavor spokesman declined to comment.

The company first filed for an IPO in May, slating its debut for summer. But last month, Endeavor shifted the timing to the fall. At the time, the company didn’t explain why, but media reports cited a potential acquisition.

The Beverly Hills-based firm was said to be reviewing a deal to buy hospitality and live-events company OnLocation Experiences for as much as $700 million.

For the six months ended June 30, it posted revenue of $2.1 billion, up from $1.5 billion in the year-ago period, the filing said. The company’s losses for the six-month period shrank to $192.6 million from $404.5 million.

Endeavor plans to list its shares on the New York Stock Exchange under the ticker symbol “EDR” at a time when companies generally are having a tough time going public.

“There’s been a chill since August,” said Kathleen Smith, principal at IPO research firm Renaissance Capital.