Hedge fund legend Julian Robertson Jr. sees stock market valuations as "very high" and worries about a bubble forming.

The Tiger Management founder made the comment Tuesday at the Delivering Alpha conference presented by CNBC and Institutional Investor.

Central banks including the Federal Reserve should get the blame for the high market valuations through their programs to keep rates low and make sure investors did not have other alternatives to get returns.

"The market as a whole is quite high on a historical basis," he said. "I think that's due to the fact that interest rates are slow low. But there's no real competition for the money other than art and real estate."

The Fed and others have kept rates low since the financial crisis in an effort to spur growth. The U.S. central bank is in the process of gradually raising rates, but the Fed benchmark is still low by historical standards.

"I think we need interest rates to appreciate, to go up, because I think we are creating a bubble," he added.