SHANGHAI, Aug 27 (Reuters) - China's major stock indexes rose on Thursday as a strong rebound on Wall Street helped calm global markets after days of wild volatility.

The CSI300 index rose 2.2 percent to 3,092.81 points by 0126 GMT, while the Shanghai Composite Index gained 1.7 percent to 2,978.03 points.

China CSI300 stock index futures for September rose 4.1 percent, to 2,938.6, 154.21 points below the current value of the underlying index.

The Hang Seng index in Hong Kong was up 3.2 percent, to 21,758.62 points.

Ironically, U.S. stocks rallied on Wednesday on expectations that the Federal Reserve will hold off from hiking interest rates next month due to mounting global uncertainties, including China's sputtering economy and tumbling stock markets, the very factors that prompted heavy selling in the previous sessions.

China stocks fell on Wednesday, taking their losses to over 20 percent in just five days, underscoring fragile investor confidence and deep doubt over whether the central bank's latest cuts in interest rates and reserve ratios on Tuesday could stabilise the economy.

(Editing by Kim Coghill)