The soaring stock market is out of synch with the more sluggish economy, says Stephen Schwarzman, CEO of Blackstone Group, the world's biggest private equity firm.

"When you have an economy that grows at 2.5 percent, 2.75 percent, and a stock market that goes up 27 percent, [that] seems somewhat disconnected," he told CNBC.

GDP expanded an annualized average of 2.4 percent in the first three quarters of the year. The Standard & Poor's 500 Index has generated a total return of 28.5 percent so far this year.

Editor’s Note: 5 Reasons Stocks Will Collapse . . .

"The economy is improving pretty modestly," Schwarzman conceded. "I think there's a lot of bullishness [in the stock market] that feeds on itself. The real world is moving ahead. But it's not barreling ahead."

While Schwarzman declined to forecast whether stocks have a correction in store, he said, "it seems a low probability that markets continue going up at 27 percent."

Meanwhile, he expressed approval for the Federal Reserve's decision Wednesday to curb its bond buying. "I think the Fed was basically trying to fight the dysfunction of Washington by just keeping the economy on an even keel," he said. "They've had enough of it."

Beth Ann Bovino, chief U.S. economist at Standard & Poor's, put the Fed's move in more positive terms.

"[The] decision by the Fed is a vote of confidence in the sustainability of the economic recovery," she wrote in a commentary obtained by The Wall Street Journal.

Editor’s Note: 5 Reasons Stocks Will Collapse . . .

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