Signs are surfacing that international hot money is bowing out of China.

In July, the country reported 171 billion yuan ($25.2 billion) of increased money supply in circulation from foreign exchange inflows, including the trade surplus, foreign direct investment (FDI) and international hot money, according to the central bank.

Since the trade surplus and FDI stood at $28.7 billion and $6.92 billion, respectively, the hot money outflow was estimated at $10.4 billion in July, said a recent report by the Research Center for International Finance under the Chinese Academy of Social Sciences (CASS). This is the third consecutive month of net outflow after torrent inflows in the first four months of this year.

Risk aversion came to the fore as fears about the Greece debt crisis abounded, promoting speculative investors to turn to the safe U.S. bond market, said Zhang Ming, General Secretary of the CASS' Research Center for International Finance.

Meanwhile, investors have lost some interest in China as expectations for a rise in the value of the yuan weakened and policymakers poured cold water on the hot property market, he said.

The Chinese currency, the yuan, lost 0.52 percent of its value against the U.S. dollar in August as the market confidence for the U.S. economy picked up.

But still, guards are necessary against speculative capital, which may come roaring back later this year, said Wen Bin, a senior analyst at the Bank of China Ltd.