The Federal Reserve, which ends its two-day September meeting Thursday afternoon, has held interest rates near zero since December 2008. It has not raised its benchmark fed funds rate in more than nine years.
Emerging-market economies are slowing down significantly, and a Fed rate hike would probably increase the slowdown, Rubenstein said.
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Recent global economic data have been more "challenging" and present a case for the Fed to hold off on liftoff, said Joseph Sullivan, chairman and CEO of global investment management firm Legg Mason.
"Now, there are those who I think dismiss that, or don't think that the Fed considers that as much as I do. But I have to believe what we're seeing out of China and some of the other markets has to impact at least, or enter into the thinking of the Fed," he told "Squawk Box."
Sullivan said he hopes the Fed moves toward normalization of interest rates on Thursday, but said stock markets remain "fragile" at the moment. That, too, may stay the central bank's hand.
As for the private equity industry, sluggishness in emerging markets is not a problem because firms tend to buy when there's disequilibrium and uncertainty, Rubenstein said. The decline in the developing world might be a good opportunity for private equity, he added.
Rubenstein said he doesn't fear a rate hike either.
"For our business it really isn't going to be that cataclysmic or really that dangerous because the truth is when interest rates go up, prices tend to go down in public markets. Therefore prices are less expensive and it's easier to buy things," he said.
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The Carlyle Group, one of the world's largest private equity firms, has $193 billion in assets under management, according to its website.
At present, many private equity firms are finding it difficult to purchase assets because prices are too high, and that will change as interest rates begin to rise, Rubenstein said.
He said the real issue is not an interest rate increase, but credit availability, and he doesn't see that drying up.